If an OEM installs the 64-bit Windows 7, but its being incompatible with drivers, etc. is it possible to downgrade back to 32-bit while still keeping the SLIC/OEM license? I know we need a 32bit COA and a image of 32bit win7. but does the SLIC/DMI change?
In all honesty, I have not had a single hardware issue since moving to Win7 x64 from Vista x86. In a number os cases I've found my hardwre - ranging from 1-6yo actually works better than either Vista or XP x86. If you are .in terms of x64 drivers officially released, google the particular driver and see if there is either a patched or opensource alterntive.
COA is version independent. If you are issued a license for Windows 7 Professional OEM, then it is for x86 and x64, you just can't legally have both installed at the same time on the same machine.