Descending with the 757, can anyone help?

Hello all,First I have to say I'm just floored by the PMDG products. If they cook like they create airliners I'll eat their burned food. I had almost completely switched to the *other* flight sim but the PMDG 757 got me hooked on FLY 2 again. No flame intended, I'm truly multi-simual. Is that a word?Anyway... I've got the FMC to do everything just great. I take off, VNAV/LNAV takes over, I cruise along and then..... The problem is the descent doesn't work as cleanly as I'd like it to. The default TOD picked by the FMC causes the aircraft to overspeed without the constant attention with the airbrake.If I do an earlier descent by selecting an altitude with the MCP, I descend to my selected altitude at the next waypoint but the FMC does not switch from MACH to IAS like it does on the climb. So, I have to watch to make sure I don't overspeed and set the speed correctly.Is there anyway I can set up the FMC to do all the work from takeoff to my last waypoint (around 2000-3000 alt) where I take over the landing? Am I missing something or is that just that way it is? I realize I'm trying to fly the 757 hands off but I gotta do the dishes and stuff. Don't worry, if I ever really fly, I'll stay put in the cockpit. :)Thanks!Tim Dobrowolsky