Conditional formatting (no borders; range B2:D5 in the example) is lost after saving the file.
Example: https://gofile.io/d/3AMBs3
Hi,
Please try again with the latest bugfix version from our BugFixes page or NuGet.
Does this solve your issue?
Regards,
Mario
Seems to be working 
Thank you!
Will a stable version with the fix be released soon?
Yes, it should be available before the end of this week.