For the past month or two (I'm not actually sure WHEN it stopped working) I haven't been able to successfully boot (any) Windows installations using libgfxinit. 

Mid-October I had created some builds that worked, but I'm not sure they were using master or something else at that point (only kept the binaries unfortunately).

The symptom is that when I select the Windows boot manager from Grub, I get a very regular-looking, TV-static like screen, then black. From the HDD activity, I can tell the boot is continuing but the graphics don't recover.
Interestingly, if I then force-powercycle the machine, the Windows bootloader does successfully enter its "Recovery Environment" or whatever that is. I can try to choose an OS to boot, but after that the same thing happens.

Is this a known bug / issue?

I'm building the latest master for the X210 using mgj59's port.