Working with other animators but they see empty frames

So was planning a collaboration effort with some other animators but we have run into a major bump. When we transfer our project to someone in our team they cannot see any drawings. The frames are still set in their layers but totally blank in the work area. Another thing I looked at was the colors and all there is was the"Vectorized Line." There is no other color. Ive tried selecting around the screen in hopes that some reason the lines have become transparent but there is nothing. I zoomed out to see if some how they became misaligned in the project but nothing as well. Tested the preview render nothing but white. Would Zip do anything to the files?. Is there a certain way you can transfer a project file to another and we are just doing it wrong? If so, I’d be very happy to hear it.
Thanks

When you transfer the project are you transferring the entire project folder? How are you sharing the file?

use same version… you might be using different version of harmony, sad to say harmony has no backward compatibility.

If anyone cares. Got this fixed a while and thought I best list that fixed it. So if you get a file from someone else using the same program the file will have to be changes to share. I do not know why I didn’t think about this, and DessieX knew what the problem was but I skimmed right over it my bad.

We have the same version of Harmony, and the whole file. If you click on the file and drag and drop the file on harmony then it opens correctly. Very odd but it works.