I can't stop the magic mouse from vertical scrolling in GIMP, which zooms the view insanely in and out when the command key is down, or which blasts my fine tra

I can't stop the magic mouse from vertical scrolling in GIMP, which zooms the view insanely in and out when the command key is down, or which blasts my fine tracing job to hell at times. I can't stop horizontal scrolling when I absolutely don't want it. I tried all the mouse settings and probed the mysteries of GIMP key remapping (it still may be there) Excellent resolution, but sometimes freaky to use. I really don't want to pay for software to fix all this. I got an MX keys keyboard because Apple doesn't sell a lighted one except in laptops.