@SEEN88
The "Download Project" functionality works on my end File > Download Project produces a tarball named "projectname.tar.gz"
Are you running the latest version of the image? Maybe this is a Windows thing?
As for Group coding Honestly it is not a big change there is a "--collab" cli option, the problem is that unless we do a custom login splash page where a user enters their name all the users show up and anonymous. (I used to do this for Taisun you can see a version of that here https://gitlab.com/thelamer/taisun-dev )
But without c9 central servers the collaboration is a bit hit and miss and we intentionally left that out, feel free to modify "/root/services.d/c9/run" and add the collab flag to try it out.
Edit : it does check the platform https://github.com/c9/core/blob/d8917f33fd7d32141d895fb7de530cfee2a416cf/plugins/c9.ide.download/download.js#L121 will add this in