methodologie for huge SolidWorks assemblies > 10 000 components

Hello,

I use cloud 3DEXP

I would like to know if it exists a methodologie or tips for working with SolidWorks large assemblies

I use assemblies between 3000 and 40 000 components.

I have a lot of instabilities:

-time to lock 4000 components sometime takes 2 min, sometime 20 min

-sometime I have error message during save to 3DEXP, I do it again and no error messages!

-A lot of files have a status "file is modified insession" with no reason !

-...

thanks