I have an issue with the PlusTools from Wordfast: I was able to install them properly, it works and I can even align two files. Once aligned, the issue is that I can't export the TM, which is very frustrating. In my company, the only person who can do it is working on Windows XP. Everybody else working here on Windows 7 just can't export their TM...
Windows 7 vs. XP shouldn't matter to PlusTools. What does matter is the Word version. As stated on the download page: "PC/Windows with Word 97/2000/2002/2003 only."
I personally don't use PlusTools for alignment, so I can only refer to this article: http://www.wordfast.net/?kb=139-27
The development of PlusTools stopped years ago. Their are several good and actively developed aligners out there, for instance the Wordfast Online Aligner included in Wordfast Anywhere and LF-Aligner, both of which are free. Have you tried them?