Hi Mat - it looks like you are using an older version of the trial, the 1.0 version.
There is an updated version 1.1 which fixes this problem, if you uninstall your current trial version, and download and install the latest one from here: http://moi3d.com/download.htm then that should get things working for you on Windows 7.
the updater isnt working, its int he install directory and still says it cant find the path.
Im running 64bit Win7, so its installed in the x86 program files directory, could that be
a problem?
That other updater is only for updating the 1.0 full release version to 1.1, not the trial version.
You need to uninstall the old trial version you currently have, then run that new version full installer, and then you should be working under Windows7.