Youse guys are really making this too complicated. Micro, you've already done the hardest part, adding the beta flag. Seriously! 
You can get 8057's whether you're running Ver 6 or Ver7, and whether you're running Core 15v2.22 or 2.25 or any combination of the foregoing. The hardest part is patience. Micro, yhm and it's Core 2.22 and all you do is overwrite Core 2.25 with it and you'll be good on Core v2.22 until the beta servers go offline again and they send you a 762x which needs 2.25 to run. After that when you get back to the "regular" beta WU's again (8018 and hopefully a lot more 8057's) you just overwrite 2.25 with 2.22 again, so Micro, keep the one I e-mailed you in a holding directory.
K? 
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