Thank you everyone for all your answers. It’s probably a network problem because after reading your post, I try something last night :
- I turned off every Mac
- I turned off the NAS
- I turned off internet box
- I turned off the switch (verifying there is no loop on it)
then
- I turned on the switch
- I turned on internet box
- I turned on the NAS
- I turned on the Mac
- I turned off the “File Vault” on one Mac to test
- I relogged every user to the NAS
- I reinstalled SketchUp
- I launched a new SU project, upload from the NAS (like I used to do)
Since yesterday, I had no crash at all… Let see if it keeps working.