Captivate Compatibility

One of my colleagues is on v8 of Captivate and I am on v7 and now I can't open the files she has created.  If I go to v8, will I still be able to work on v7 files that I have previously created?  Likewise, if I create projects for my clients in v8, will they be able to edit the unpublished Captivate files? If yes, what is the minimum version required to do so.

PS - It would be awesome if Adobe actually thought about backwards compatibility.