I have this CPU slowdown utility around for other games I play. It's good for slowing down older games where various things have problems like map scroll speeds.
The utility I am using is Mo'Slow for Biz ($25 USD):
http://www.hpaa.com/moslo/compare.asp
A shortcut like this is all that is needed:
C:\MoSlo\MoSlo.exe /q/15/m2 F:\Games\BoA\BoA.exe
This accomplishes the following. Load BoA at 100% CPU speed.
When I hit the toggle keys (LCTRL-LALT-RSHIFT), then slow BoA to 15% CPU. You get a confirmation beep. Hit it another time and you get another confirmation beep and are back at 100% CPU.
Simply set up your turn at 100% CPU, zoom out, hit the slowdown toggle, and hit F9 to process the turn. Then, sit back and watch the action unfold.
Initial testing with one scenario shows that the net result on a Mobile Pentium 4 2.8/GHz processor is 1 day takes about 0.5-1 second to run (longer if battles take place). Of course, this is totally configureable.
Not as good as having an in game option to tailor this, but works better than having nothing.