I had the exactly same problem... i couldnt boot into vista.
After setting active partition the vista partition and fixed the winload.exe message with Vista dvd, i used EasyBCD.
Added the MAC entry as generic ix86.
Set active partition Mac OS X
Chameleon showed up
Vista Worked with 2 boot selections vista-Mac (with mac going into chameleon loader)
But after getting into Vista i couldnt open BCD
error:
"Valid BCD Registry not Detected
Easybcd has detected that your BDCD boot data and MBR are either not from the latest version of Windows Vista, or don't yet exist.."
Just go to cmd and set partition vista active
diskpart
list disk
select disk x (select your disk)
list partition
select partition x (select your partiton you want to make active)
active
exit
exit
Open EasyBCD
Delete MAc OS X entry
Set Mac OS X partition active again through Vista
And everything works now without second boot selection