Open SBpro22 file on SBpro6

Hi everyone.

I use SBpro6, and my colleagues use SBpro22.
Usually, I’m able to open their files with no problem.
But there is one project in particular I’m not having the same luck. When trying to open it in SBpro6, the message says:
“Could not open project
This project was saved using a newer version of Storyboard Pro and contains unsupported features.”

I tried to open the file and look for the unsupported features to get rid of them and make my file backward compatible, but I couldn’t locate which feature that might be. There doesn’t seem to be anything unusual about it.

I’m still able to copy individual drawings and paste them on SBpro6, but it’s a long project, and that would cost me long hours of work.

Any idea on what would be possible to do to make this project compatible with SBpro6?

Thanks in advance,