Cannot use BZ with windows associations with virtual machines

The problem is in BetterZip application - it has no OS Type code (creator) assigned.

I can provide a quick solution for you and others to solve such problems.

1. Open application's PkgInfo file (for BetterZip it will be "/Applications/BetterZip.app/Contents/PkgInfo") in TextEdit or other editor. Change "????" to something else, for example "BZIP" (4 capital latin letters). So, the entire content of PkgInfo file will looks like "APPLBZIP"
2. Open applications Info.plist file (for BetterZip it will be "/Applications/BetterZip.app/Contents/Info.plist") in TextEdit or other editor (for example, Property List Editor which comes with developer tools). Find "CFBundleSignature" line (or "Bundle creator OS Type code" field in Property List Editor). Change the following line "????" to something like "BZIP" (the replacement must be the same as in "1.")

All done. Now we need to tell Mac OS X that application was changed a little, there several ways to do it:
- move (copy not required) to some other location (I use Trash for such purposes, but you can use Documents for example :) and then move it back to "/Applications"
- touch it using Terminal
- other less handy ways

After that start your Virtual Machine and click Applications -> [Shared Mac Application] Populate. Wait for a while, application will be in Parallels Shared Applications folder in Start menu.

I attached an Apple Script file that will do the same thing. It is very convenient and documented. Just open and run it (push the green Play button). It will ask what application to modify and what creator OS Type to assign to it. You can say "Cancel" in any time. Also you can revert to the original by entering "????" creator OS Type code.