Unarchiver just stopped working for me. Clicking a .zip file invokes it but no windows, no progress, and the app refuses to quit afterwards.

I downloaded a new copy but - in classic kafkaesque fashion - the download is a .zip file.

If I open it with Stuffit expander I can see a folder being created in the same directory but it auto-deletes as soon as the process is complete.

Any ideas? is my Mac haunted?