I have not been able to reproduce this issue either so far - tested mIRC 6.35 under Windows 7 RC build 7100. If I select the desktop and hold own F5 the desktop refreshes and the icons flicker, as expected. If I then switch to mIRC and open several windows, such as channels, and switch between them using Control+Tab, or clicking on the switchbar or treebar, the desktop icons do not flicker.
I think we may need to narrow this down a little - for example, if you turn off the treebar and switchbar through the "View" menu in mIRC and then Control+Tab to switch windows, do the desktop icons still flicker?
