How is this possible?
# Associate .qtv files
WriteRegStr HKCR ".qtv" "" "QuakeWorld.QTV"
WriteRegStr HKCR "QuakeWorld.QTV" "" "QTV Stream Info File"
WriteRegStr HKCR "QuakeWorld.QTV\DefaultIcon" "" "$INSTDIR\ezquake-gl.exe,0"
WriteRegStr HKCR "QuakeWorld.QTV\shell" "" "open"
WriteRegStr HKCR "QuakeWorld.QTV\shell\open\command" "" '$INSTDIR\ezquake-gl.exe "%1"'
# Associate .mvd files
WriteRegStr HKCR ".mvd" "" "QuakeWorld.MVD"
WriteRegStr HKCR "QuakeWorld.MVD" "" "Multi View Demo File"
WriteRegStr HKCR "QuakeWorld.MVD\DefaultIcon" "" "$INSTDIR\ezquake-gl.exe,0"
WriteRegStr HKCR "QuakeWorld.MVD\shell" "" "open"
WriteRegStr HKCR "QuakeWorld.MVD\shell\open\command" "" '$INSTDIR\ezquake-gl.exe "%1"'
# Associate .qwd files
WriteRegStr HKCR ".qwd" "" "QuakeWorld.QWD"
WriteRegStr HKCR "QuakeWorld.QWD" "" "QuakeWorld Demo File"
WriteRegStr HKCR "QuakeWorld.QWD\DefaultIcon" "" "$INSTDIR\ezquake-gl.exe,0"
WriteRegStr HKCR "QuakeWorld.QWD\shell" "" "open"
WriteRegStr HKCR "QuakeWorld.QWD\shell\open\command" "" '$INSTDIR\ezquake-gl.exe "%1"'
# Associate .qwz files
WriteRegStr HKCR ".qwz" "" "QuakeWorld.QWZ"
WriteRegStr HKCR "QuakeWorld.QWZ" "" "QuakeWorld Zipdemo File"
WriteRegStr HKCR "QuakeWorld.QWZ\DefaultIcon" "" "$INSTDIR\ezquake-gl.exe,0"
WriteRegStr HKCR "QuakeWorld.QWZ\shell" "" "open"
WriteRegStr HKCR "QuakeWorld.QWZ\shell\open\command" "" '$INSTDIR\ezquake-gl.exe "%1"'
EDIT: I TRIED THIS ON ANOTHER COMPUTER AND IT WORKED FINE. YOU CAN DELETE THIS THREAD!