Two mouse pointers are visible on the red allegiance launch screen in beta mode. One is the windows pointer, the other is the allegiance pointer. the windows mouse pointer is only visible outside the screen footprint of the previous "splash screen." Not that big a deal but someone should know.
i only get this if some window like an antivirus scan popus up after allegiance launches, that window activates so windows shows the mouse, but alleg is still full screen, so it shows alleg.
try alt-tabbing out of of alleg and see if a window has sprung up behind alleg
I remember having this error in other DirectX Applications when i use the "mouse trail" feature of windows XP.
Try to turn that off if you happen to use it.