The corrupted file issue I ran into is just a misused autosaving mechanism of OS X Lion: You open a UFO package, the app internally converts it to its native Glyphs document, you then edit the font, the autosave triggers off and saves the Glyphs document over the UFO. If you change the extension of such a corrupted file from .ufo to .glyphs it will read as nothing had really happened. Before this gets fixed, you can restore pre-Lion saving behavior in the app's preferences or just duplicate the opened UFO as a Glyphs file before making any edits to a font.

You might also disarm the control freak portion of Lion that forces the damn versions thing on you. There is a preference in Glyphs that will do this for you.
Are you using the current version of Glyphs? Since Georg posted the update, I have had far fewer problems.

Chris, thanks for pointing that setting out. Versions is an even bigger disaster than Time Machine, I can’t imagine why anyone would use it for anything.

Glad to help a fellow traveler to Glyphland :-)

@James: IIRC you used to praise Time Machine. What happened?

I’ve heard about this “corrupted” problem with Glyphs files. Scary. So it has to do with Lion. Seems I’ll stick to Snow Leopard as much as I can.

Time Machine is terribly unreliable. It just stops working with no explanation, requiring users to run through a series of possible fixes until it works again. This is exacerbated by Apple’s continued inability to produce a reliable automatic external disk mounting daemon, something every other UNIX vendor worked out in the 1990s. In worst case scenarios Time Machine stops recognizing the backups that it created, and will not back up anything else to the same disk partition until the old files are gone.

On top of the reliability issues, Time Machine’s interface is an atrocity; breaking away from anything resembling Mac UI standards for some addled Star Trek themed nonsense, reliant on cheesy 3D effects that have never been optimized to run quickly.

Every single person responsible for Time Machine should have been run out of Apple and the entire design and codebase should have been strangled in its crib.

I'm lagging behind, using OS 10.5. Would you say that upgrading is a necessity?

The errors run the gamut from freezing when just moving a node, to not being able to export with the autohinting turned on. And the true mess begins when getting into masters. Ugh.

Upgrading probably won’t help, but a fresh install of Mac OS might. I had a lot of problems om Glyphs on my four-year-old laptop until I got a new computer this year. On the new computer Glyphs is very stable and responsive. I suspect that this is because Glyphs relies heavily on Apple’s Cocoa API and Cocoa gets mucked up over years of upgrades.

Ok I may be getting a whole new computer anyway so hopefully that will do good things. (I do get "Cocoa" error messages) Thanks for the tip.

For info, I’m using Glyphs on Lion, with disabled Versions and have no corrupting files issues.

An update for those in my situation: Upgrading to Lion really helped. There's a few weird things here and there but it seems mostly fine now.