Mac offline not able to save

Mac OS 10.14.6 by the way.

To clarify, are you using ColorSource Offline v2.6.0 or v3.0.0?  What format is your USB drive?

I'm in version 3.0.0.33 and the USB drive is MS-DOS (FAT32).

Still not able to save a file in CS 40AV mac offline.

Hmm, so I double-checked on a Mac here and it seems to be working okay.  Have you tried it with a different thumbdrive, just to be certain that's not the issue?  Is it safe to assume you've rebooted this computer a few times since installing the software?

Would you be willing to try unistalling / deleting the ColorSource Launcher program, and re-installing it, being careful of any popups about privacy / permissions?  It could be that one of those got out of sync.

Deleted the ColorSource DMG and launcher, downloaded the DMG from ETC and opened launcher, clicked on 40 AV, patched 24 dimmers and tried to save:

Just tried to run the same launcher from a flash drive and got this:

Tried re-booting/ Same problem.

I borrowed a MacBook pro with the same OS and the offline editor does save data on that machine. So something is off with my MacPro desktop system. Any ideas.

Saved the file from the MacBook on a USB drive and was able to open it on the MacPro but then I got this error:

Would you mind re-downloading the application, in this case?

I have three times. I'll try again with the MacPro in safe mode.

Same problem in safe mode.