gpu lightmapper gets stuck at the end, sometimes crashing the editor too. canceling an restarting bake doesn’t work and you won’t be able to bake on any mode, including cpu, after this has happened.
everything else works normally but unity editor always freezes upon quitting, and application cannot close itself causing you to have to force quit unity
If the crashes you are getting cause the bug reporter window to appear, please use that to file a bug report. If not, you can take a look at this Unity QA: Building quality with passion.