Incidentally, the backspace issue has been resolved as "won't fix". It is triggered when you choose a non-fixed-pitch font in the editor. They know what's wrong but are afraid to make any changes this late in the game.
Microsoft asked me to remove my link to the Avalanche beta for "security" reasons. They want to limit the beta to MVPs and selected customers. Those that don't have the August CTP by now still can't get it from MSDN--it's still not posted there. IMHO, this is a serious problem. This version is the most important of all as it includes (for the first time) the implementation of nullable types. It's essential that people download this version from whereever they can get it as soon as possible and test it.