I had the same problem and just changed the filetype from .amm to .mdb and that worked fine, no problems, after import just change the AMM filetype back if you still want to keep it as EMM makes it's own. Just to clarify if you are confused it's the AMM database file (on Win 7 located in C:\ProgramData\AllMyMovies) that you need to change the file extension of. After you import just return the ext back to .amm I had no problems with this, regardless of the ext name the file is just an access database file.
I was working in Win XP and kept getting the 'this is not a valid Win32 application' whenever I tried to use the renamed .amm file. That could be symptomatic of bigger issues with my XP setup, not sure.
I gave it a try in a Win 7 environment and it worked.
Now to try to wrap my head around all this functionality of XMM ...
Well, just purchase the program. Seems as if you haven't registered XMM. So you're using the shareware version that has limited functionality as a restriction to 50 entries.
In order to achieve what is possible, you have to try the impossible over and over again. Hermann Hesse