When I save a drawing in Easyrun 13.1 in a windows folder, it will continue to show in the application, but if I go to the file explorer in windows these files do not exist.
I went back to easyrun V 13.0 and all files saved from there are accessible in windows or from other apps.

event viewer has messages mentioning sandbox.

I recommend running it without sandboxing or revert to version 13.0 to ensure files are saved to the standard file system.
Retro Bowl

How do I disable sandboxing ?

Is that an CMS file configuration ?