That would be their fault - they intentionally provide an incomplete specification for their proprietary formats. It is a compatibility nightmare - there is no

That would be their fault - they intentionally provide an incomplete specification for their proprietary formats. It is a compatibility nightmare - there is no telling what kind of corruption or information loss an older version of the software will introduce when dealing with a file produced by a subsequent release, as there are no well defined specs to guarantee forward compatibility. Of course... you could just use an open standard file format and skip all the pain on display in Adobe's forums.