I have a custom template called 'tcz_ad_topad' that cannot be reverted in the default style, or deleted in the master style. In attempting to find the problem, I recreated another template called 'test_ad_topad' and got the same results. Evidently, it has something to do with the '_ad_topad' portion. I'm using 1.2.0 Beta 4. I should also mention that I am able to delete/revert the same templates on my live site, which is running 1.1.4.