Did you try uninstalling ZA?
Have you tried the latest stable release (4.16.6) or the latest Beta (4.17.4)?
See whether they're any better (sometimes it's just that certain versions cause problems for some people, but a different version will work fine).
Have you been able to use any earlier versions of LW with Vista? If you haven't tried an earlier version, here's a link to download 4.14.8...see whether that one loads.
LW Basic 4.14.8.exe