https://bugs.winehq.org/show_bug.cgi?id=38205
--- Comment #8 from Erich E. Hoover erich.e.hoover@wine-staging.com --- (In reply to Hans Leidekker from comment #6)
... Can you retry with current git? If it still fails, please attach a +msi,+msidb trace. The regression reported by Béla should be fixed by db3fdbe1e3570f9b79f5c00fd166881e78c5f9a6 (which is an improved version of the patch attached here).
I was testing with the latest git, but I now believe the problem is not actually in Wine - it appears that the installer package I was editing became corrupted at some point. It's odd that before that commit I could still edit it, but anyway - I don't think the commit is actually responsible for the problem.