If apps are shown as incompatible with your device get a modded Play Store apk that has restrictions removed, e.g. http://xdaforums.com/showthread.php?t=1580827
Certainly that issue shouldn't be in this thread as it's not caused by/related to the extension.
I have tried that modified market back when it was 3.5.19, and it would always give me connection errors, much like the legacy play store did.
As far as requests in this thread, there have been others in here. The original extension thread is full of people requesting others with the extension to download apps for them when the extension has not worked for them. There was a request a few posts up, and I think the person who made this new modded extension posted the app for them.
I can try the modded market again to see if I have any luck with one of the newer versions.
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