Cannot Sign In to Mac App Store - Tried Every Way Possible & No Progress.

I'm so disappointed that Apple has left so many of us hanging like this. I've submitted several support inquiries online exactly as their site instructed me to & received no response. Not even an automated one!

Here's what I sent to their Support & if any of you can help me out, I'd be forever grateful:
--

I'm a very savvy and technical user who is also on your iOS & Mac Development Program.

Anyways, I downloaded & installed the 10.6.6 Combo Update on my work iMac & had no issues accessing the Mac App Store.

I used the exact same Combo Update on my home iMac & had no errors, however, when I launch the Mac App Store, I can click anything and get a response BESIDES Sign In, Account or BUY NOW.

For whatever reason, my home iMac won't let me log into my Apple ID (please don't ask me to reset my password or something try to reboot; trust me, I wouldn't be writing you if it wasn't serious. I tried everything, including a reinstall of the 10.6.6 update. Nothing changes the fact that it won't give me the sign in dialog where I'd type my Username & Password).

PLEASE HELP - I really want to anxiously start buying some apps & cannot log into this store no matter what I try. I'm convinced it's absolutely a software bug.

Do you perhaps have an INDIVIDUAL INSTALLER of the Mac App Store that I can download? Please don't tell me to redownload the combo update. I did three times already.

Also, both the Mac App Store on my work & home iMacs read Version 1.0 (54) - so why would one work & the other not work???? I'm convinced that there's a small yet critical bug here & that I'm not the only one having this issue. It's really upsetting that Apple released such poortly tested software that apparently has so many people unable to use it.

I hope that you can help & make this work for me ASAP.

Please respond ASAP - I really hope someone actually reads this issue & sends me a useful reply, and not some canned message.

Thank you.