All of these are from the experiences of myself and colleagues, and some of these are noted in Peter's blog post in CAD Booster (and were experienced by us), so check that one out as well:  https://cadbooster.com/37-things-that-confuse-me-about-3dexperience/

These are listed in no particular order, but I tried to keep related issues together.  Also, I wrote about half of this while waiting for a save-to-3DX command to finish (it never did, I killed Solidworks and tried again).

1. Sometimes your login seems to just fail.  Or you get logged out mid-session and it locks up Solidworks.
2. Saving to the platform will inexplicably lock up Solidworks on occasion.  Go take a break outside.

3. The main Search function is nearly useless.  Every configuration is a search result, so any parts with configurable lengths (which have a different part number per length) will show up.  Ditto for an assembly with different options as configurations. Good luck finding the "Default" config if you don't specifically ask for it, it's result number 27! (true story).  If you specify "Default" in your search then you get a bunch of routing components first...

   

4. Whew, now that I've found my result, I can... open it in Solidworks!  Only by right clicking -> Open.  If I just double click, I get a preview window and some properties.  If I drag it into Solidworks, it may load in Solidworks.
5. Dragging parts into Solidworks from the platform works about 75% of the time.  Not 100%, not even 90%.

6. Want to quick filter search results to show assemblies?  Nope, you can drill down to them with the "6W" tags through at least 3 clicks, but since PDM added quick-filter buttons, 3DX must not be allowed to have them.

   
7. Did your search result show a CAD family? Great!  What is a CAD family? You can't do much with that either, besides delete it or open it. Definitely can't change maturity.  But it does help increase the number of search results.
8. If I want to, say, lock a file that I managed to find in the search results... I can't.  There's no option to.  Want to change the maturity state?  Nope, can't do that either.  Download? No way. Mostly, search results tell you that the file exists and now you have to find the app you need to do what you want with it.  Happy hunting!
9. There are too many "apps".  I don't need an app for a calculator, or the globe, or 50 other things.  I just want to work with my files.

10. Many of the apps that I can see, I can't use due to my license/role/whatever.  If I can't use it, why does it have to clutter my workspace?

    

11. Why are there 3 icons for 3D Play!? (see above pic)

12. What is this Me/Company/World nonsense?  I've never needed to use the Company/World tabs.

    

13. What is the difference between a "Dashboard" and a "Cockpit"?  I still don't know. Even the search bar seems to think they are the same.

    

14. There are too many search bars!  It's very common to have 3+ on the screen at once.  This pic shows 4 (technically 5).

    

15. Related note: Options buttons that don't give you the options you expect.  Think this prominent Gear icon will give you platform options?  Think again!  It just changes the veiw of your many icons so you can choose how overwhelming they are.

    

    Think this Preferences option from the home screen drop-down will do more?  Nope!  

    

    It gives you the name of the platform you're on, with a text field that you can't edit but you can Save, apparently.  

    

16. The number of actual options is ridiculous and impossible to filter through, if you can find them.  See how small that scroll bar on the right is for just one of the sections on the left?  Oh, most of those options don't actually apply to you given your roles. Just FYI.

    

17. Wait, there are options for my options?

    

18. What even is a 3DSwymer?  Oh, it's just a basic user swimming in too many apps.  Collaborative Industry Innovator?  That's who can change file maturity and stuff - but not one who can use Solidworks.

    

19. The Bookmark Editor app is actually the most useful app - and rarely used for editing bookmarks.  Want to move a file from one collaborative space to another?  Oh, that's in the Bookmark Editor app.  Right.

20. Can we get some color here please??  (Bookmark Editor again)

    

21. I can use Bookmark Editor to download files, but if I download them more than 1 at a time, they come in subfolders marked with... their file name.  Which is not their title - it's a platform-assigned ID which you can't change.  Good luck figuring out which file is in which folder!  Here I downloaded some of our Solidworks macros. I think.  There is 1 macro file per folder, naturally.

    

22. On that note - files have "Names" and "Titles".  Title is what you can change, Name is what you can't change.  Got it?  

23. Why did I download a file?  I need to edit a non-CAD file - those you have to first Lock, then download, then edit, then re-upload, then unlock.  Except for non-CAD files, you don't Lock/Unlock, you Edit/Finish Editing.  Which locks/unlocks the files, of course.

    For a CAD file (the button is called "Reserve" not "Lock". Just a heads-up):

    

    For a non-CAD file (this button is called "Modification Commands", by the way - no Reserve/Lock button here!):

    

24. A note with lock/unlock: when you do a Save As, there's an option to unlock the file when it finishes the operation.  This is great except that it unlocks it anyway.  No way to keep a file that you just created locked by default.
25. Now don't you dare edit those non-CAD files in your 3DX cache on your hard drive.  If you do, they could be overwritten should you decide to update your file locations settings to "refresh" your cache.  No, you want to edit your cloud-based files anywhere but the cloud-based cache, to keep them safe.  From the cloud.

26. Speaking of file locations, did you manage to set those to point to 3DX?  Congrats!  Now, you'll always be up-to-date with your templates and everything... Guess what?  You won't, unless you manually update them.  So you go online, and hit the Update Cache button right?  Nope.  Delve into Options in Solidworks, find File Locations, select the location, then hit Update.  Too easy!

    

27. Don't yet have your templates set up?  That's OK, it is possible. Some templates auto-populate in your New File templates in Solidworks, but some need to be pointed to a bookmark.  But no one tells you that, or which ones are which.

28. Want to sort your templates by type?  That is a great idea if you've named them appropriately.  But if you used to rely on file extensions (.slddrt, .drwdot, etc) you're pretty much out of luck because you can't view file extensions on the platform without multiple clicks into the properties or some unintuitive wizardry - wizardry which is different between Bookmark Editor and Search. This also really stinks when you have pictures on the platform (jpeg? png? who knows?) or a folder with templates of various types...are these all the same kind?  Nope, mix of slddrt and drwdot.

    

29. There is no way to see the Save With Options dialog (which shows the errors preventing a save to 3DX) without performing a local save first.  Usually that's fine, but for large assemblies it really stinks to wait 15 minutes or more and then find out that a single file is blocking your save action.  So you fix that error and then wait 15-30 minutes and discover 3DX is mad about another file now!  It's also not consistent about which files it's mad about - especially if you have virtual subassemblies.
30. You cannot save an assembly if a part within that assembly has had a configuration deleted and that configuration is used elsewhere on the platform.  I get it, this keeps references from breaking.  So if I have an obsolete model or a dummy model I need to go open that, then change the configuration of the part in question and save it (which will probably produce save errors).  Or I could just delete the obsolete model...
31. Except deleting on the platform is very challenging - any reference to the file to be deleted must be removed first.  Got 5 configurations of an old assembly referencing an old part?  Gotta update those 5 configurations first.  Bet you can't delete that old assembly either.  Why not just list which assemblies will be affected and let me acknowledge it?
32.  Did you finally delete the file?  Are you sure?  It's still there!  Except it isn't, things just haven't updated yet.  Give it a few minutes. This is very confusing when trying to search for and delete duplicate files or similar files.

33. Now we get to adding content to the platform.  Oh, it's done with this big + sign in the upper right corner correct?  Wrong.

    

34. I'll just drag and drop my files onto the platform.  Smooth!  Except don't do that for CAD files and templates, because then they will be considered "documents" instead of CAD files and won't work with Solidworks.  You need to save these files to the platform from within Solidworks.  But no one tells you that.
35. By the way, sheet formats (.slddrt) are not considered templates and cannot be saved to the platform, they must be dragged in from file explorer. Makes sense.

36. Drawing templates (.drwdot) still need to be saved from Solidworks via this new command:

    

    But if you save the drawing template the old way with a Save As, then the template will be in Draft state and no one else will see or use the new template you just made...

37. Wanna make sure you have a local copy of all the files you need?  There is no version of "Get Latest Version" as PDM has.  AKA I had an issue with my local cache, and after I cleared it (which 3DX is not smart enough to keep locally modified files so there's a huge risk of losing work), I had no easy way to get those files back.  When I opened a large assembly, every component was suppressed because it could not be found.  I can't tell Solidworks to look at 3DX for the files either, so I had to open the assembly in Bookmark Editor (because of course), then expand it out to see all the files, then select all of them and tell Solidworks to open them all.  Of course Solidworks crashed after about 100.  So yeah that's the best way to Get Latest on files - open hundreds in Solidworks individually so they are cached.  Opening the assembly does not cache them.  C'mon Dassault.
38. Locking a file locks it to you - not to a specific computer.  This sounds nice, until you realize that if you work on a file on one computer and then switch to another without saving to 3DX first, you won't know that you're out of date on the second computer.  There's no way to see which computer locked the file "first".  This makes it much more likely that you'd be stuck with local changes on one PC that you can't save into the platform anymore because it will be "out of date" when saved back to 3DX from the other PC.

39. Sorting by Lock status in the SW task pane is worthless (they just get mixed up in a different way):

    

40. The 3DX search option inside of the Replace command is just broken.  There is a Solidworks (2023) hotfix for it, but that hotfix required 20 minutes of messing around with logging in after being installed, and then simply stopped working a week later. I've stopped using 3DX when doing the Replace command because it locks up Solidworks seemingly half of the time as well.

     

Now don't get me wrong, there are some benefits to the platform, and a couple of spots where it integrates well with Solidworks. However, those few things are just not enough to overshadow the sheer number of issues and lack of coherence in the 3DX platform. It is very obvious that the platform was created by people with ideas for managing files but not people who need to work with them in Solidworks (indeed, Solidworks compatibility was added after the fact, not from the get-go).  Right now my advice is: stay away!  Check back in 2 years. Or 5. Or whenever Solidworks announces the impending death of PDM.