Dear James: Thank you for the offer to assist with this issue. I have NOT filed an official bug report with WINE bugzilla as I am training to ascertain the exact issues involved. I have not done regression testing before, so it would take me a bit of time to review all of these materials. I have indeed used Mike Kronenberg's WINE binary builds to run this Windows program under Mac (you will see this in the documentation) although I have tested it against numerous WINE builds from source as well. Since there was no improvement to build from source I simply recommended using the precompiled binaries from Mike. It is indeed possible to get a copy of the Firefly program. It is copyrighted but available free of charge (see download link below). You can download the binary for Mac from the public download page but will need a password to unrar them. Actually if you just complete the registration e-mail form (included in the quick shart guide) and just mention that you are working with Thomas Patko (the lead developer is quite familiar with me). http://classic.chem.msu.su/gran/gamess/macosx.html We are also now testing the new 7.1.G binary for Mac now as well (last official release it 7.1.F), and I can give you the download password and links to this directly as soon as you are a registered PC GAMESS / Firefly user. Thanks, Thomas