My apologies. When I read the following;
-open the recovery-clockwork-22.214.171.124-inc_PB31IMG download. extract it first if you need to. inside there is an image called "recovery-clockwork-126.96.36.199-inc"....
-use your md5 summer to verify the md5 of just the image,not the whole .zip. it should be: ea382ca5809cb872d0582aa22741d592
I was looking in the PB31IMG.zip folder rather than the recovery-clockwork....PB31IMG.zip folder. Apparently reading instructions is not my forte.
So I shouldn't worry about the fact the Windows seems to think the PB31IMG.zip file is corrupt? Just go ahead and place it on the root of the SD card at the appropriate point in the instructions?