Multiple styles as one file, crash on export

Not sure if this is related to the latest appstore update, because I coincidentally decided to finally do this today, but:

I saved my original Regular font as a copy, and in the copy I added the Italic, bolditalic and bold styles as masters. Then added instances for all 4 styles.

When I export it does nothing, even when turning off the various options (remove overlap, auto hint, etc).

The console shows when trying to export:
4/23/13 7:56:26.327 PM sandboxd[7626]: ([7625]) mdworker(7625) deny mach-lookup

and if I try for a second or third time, it crashes with a segfault.

Also, I’ve tried compiling and refreshing the features, and there were no errors.

It is not recommended to put not compatible styles in one .glyphs file.

But this does not explains the error. Will have a look at it.