I added this to game/scripts/options.rpy
it gives an error at the start of the game but if you ignore it you get the standard windows mouse cursor
maybe it can help someone and it also gets rid of the ridiculous penis cursor abomination
define config.mouse = {
"default":[ ("gui/cursor.png", 18, 18) ],
"say":[ ("gui/cursor.png", 18, 8) ],
"pause":[ ("gui/cursor.png", 18, 8) ],
"gamemenu":[ ("gui/cursor.png", 18, 8) ],
"prompt":[ ("gui/cursor.png", 18, 8) ],
"with":[ ("gui/cursor.png", 18, 8) ],
"menu":[ ("gui/cursor.png", 18, 8) ] }
the solutions comes from this thread
https://f95zone.to/threads/renpy-fullscreen-mouse-problem.29776/
and is made by
Deviant Delights