Thanks for the question.
The short answer is that LocalZoom was written ~5 yr ago, and so it's not terribly surprising that it would be deprecated. Unfortunately, I moved on from UMich several years ago, and I don't really know who the present contact is for support/updates (if anyone). If someone at UM is reading, perhaps they can chime in?
If you just want to use LocalZoom, a compiled and built version is usable in the web browser. It reads files from tabix files on disk rather than uploading your GWAS somewhere.