I did all of these things also and still no Extension Rom, tutorial says 'Extension Rom' for the name btw, so if ROM needs to be capitalized you may need to fix that in the tutorial. I even did a hard reset this weekend. and still no Extension Rom. Does the name need to be Extension ROM? I took apart the stock Cingular upgrade from the HTC site and followed your tutorial to the letter. I got the 8125 close to what the stock Cingular settings are by manual configuration and someone was nice enough to post the Cingular Extension Rom contents elseware on this board. But I would really like to get the darn extension rom back on my phone.
2.If U add any cab that is not signed U must put Cert_SPCS.cab as first one to install which allows not signed cabs to install without bypassing them