Based on further review of Chromium behaviour, it seems that on both Vista and 7 it does the same procedure to check for locales, using functions introduced in Vista or earlier. The error message indicates that the default locale is defined, but default data is not, presumably referring to the manifest data for the extensions.
The nuclear solution would be to modify ntoskrnl and set its RtlGetVersion (also PsGetVersion to be sure, even though it is obsolete as of XP) to 6.1.7601, thus everything in kernel mode would think they are running on Windows 7.
Personally I connect my GPU to my 15 year old monitor with DVI, and use Realtek onboard HD audio.
On another note, the user-mode version check bypass in ntext is not as effective as possible, as I realized that VerifyVersionInfo functions call RtlVerifyVersionInfo which is presently only in ntdll, and thus uses ntdll's RtlGetVersion. However, RtlVerifyVersionInfo is a bit of a handful, and with the limitations on implementing ntext functions, it will take awhile.