As there's no free documentation available about the inner workings of the CVFs that the original software creates, dmsdos is the result from a lot of trial and error. What dmsdos does when reading and writing files may be awfully wrong according to the specification though it works in most cases.
There's no warrenty. Use dmsdos completely at your own risk or don't use it at all. Make a full backup of your data before installing and using dmsdos to feel safe.