TopMost works in Windows 8 but not Windows 8.1?

Hi,

I'm writing an application, that needs to layer it's UI on top of all other windows when active, including the Metro Start screen.

I'm using TopMost=true, and I modified the manifest to request UIaccess. I also signed the application, and put it in a trusted location...

The problem, is that this works 100% of the time under Windows 8. However, under Windows 8.1 it seems to mostly not work. It seems to randomly work a few times, then mostly not work. By not work, I mean that it only puts the UI on top of other windows while in desktop mode. When I switch to Metro, the windows disappear.

But like I said, it works 100% under Windows 8...