first off, i know nothing about the 2.6ce chip... not sure if it had the same issues and the 2.6lite with only working properly off the 2nd bank. afraid i'm not gonna be much help to you on that one. i suggest that you keep searching both here and teamxecuter's forums for others with similar probems.
as for date/time reset.. to be honest i haven't noticed whether mine has that problem or no. i've ben doing a lot of work with my box and its been unplugged like every hour.. might be the m8plus_16 though... like i said, when i had it on my 1.6 it seemed really buggy. went back to m8_16 and she worked fine.. course if you have a 1.6b then that doesn't help much
sorry i don't have any more answers for ya, but i got tired of the problems and swapped out to an X3. cuz at least team xecuter is making bioses to support that chip.. it's a shame they dropped the ball with the 2.6... a damn shame.