I am trying to save only a few components from a very large assembly to a STEP file to preserve their relative locations and generate a lightweight model for robot trajectory planning. 

I know that components must be selected from the tree (not from the graphics window) and then when the file is saved using Save As, there are two useful popup questions: do you want to resolve hidden or suppressed components, and do you want to save only the selected objects. 

My problem is that this is unreliable. It seems as though the first time I attempt to save-as only selected components after opening an assembly, it will always save the entire assembly without ever prompting me with the "do you want to save only the selected objects?" popup message. This often takes nearly an hour, because it's a very large file. Once it's done this, then I can repeat the exact same process, and it will prompt me, and I will have my exported file within seconds. I've seen this behavior whether I've isolated the desired components or not, and take care to always have the components selected from the tree. If I interrupt the command and close Solidworks, I go back to the start and have to suffer through the export again anyway.

Does anyone else encounter this? Is there a setting or preceding step that can make it so I never have to export the entire assembly first? I'm quite frustrated because it means quickly checking something can take an unreasonable amount of time in my day-to-day and prevent me from doing anything else in the meantime. I've tried looking through the forum and searching for the last hour or two without success, so am posting here. Thanks!

- Solidworks 2023 Premium SP5.0
- Windows 11 Pro (10.0, Build 26200)
- HP ZBook X G1i
- Intel Core Ultra 9 285H (16 CPUs), ~2.9 GHz
- 64GB RAM
- NVidia RTX Pro 2000 Blackwell