Automatic type propagation does not require a different code segment and a potentially different block diagram. Generics do. Auto type prop doesn't make any changes to the block diagram -- poly VIs do not shift, wire types do not change, charts/graphs are untouched, etc. Generics actually produces a whole new VI with the new type running through it.
Updated VIs to obtain hwnd by FP.NativeWindow as suggested above. Saved in LV 2013 SP1. Only tested with Windows 7 64-bit and LV2013 SP1 32-bit.
Set Calling VI Wnd Top & Active.vi
Set Calling VI Wnd Topmost & Active.vi
Cancel Calling VI Wnd Topmost.vi