VistaVS for Win7 corruption

Bug I see in =FediaFedia's VistaVS theme [link] when switched to Basic theme. Windows ,7 7600, x64

When I switch to Basic (or run net stop uxsms - which is the same), I see the following corruption in taskbar: [link]

There are transparent random parts of taskbar's UI drawn in a wrong locations, it looks like it was drawn between the taskbar and buttons (or, like if there was some bitmap that should have been opaque, but it is transparent in VistaVS, and W7 does some optimalization when it draws that bitmap over directly previous content instead of cleaning the buffer beforehand).

There are also some bugs with layout, for example the white tooltips that should appear above the blue rectngle with 2 Visual Studios are instead underneath the taskbar (and overlaid by taskbar buttons)...

I have also experienced similar corruption when a explorer run out of GDI handles because if buggy shell extension, but this is not the case as I checked the number of GDI handles allocated by all processes and it is nowhere near the limit.

Also, only VistaVS in basic does this, Aero is OK, and all other msstyles are OK even in basic.