Sure! I will post all my findings to help others as well.
Thanks for your time.
ah ok - should be fine now.
For what it's worth, I got a 5.2v 2.5a power supply. I had no reason to believe it would make a difference; but I've seen much stupider things fix dumb things.
Of course, the cursor still pops.
Dosbox definitely has a rotation, I can move with the mouse but only within a circle that snaps back to center that's def analog stick mapping. Where do I change that setting I have not come across any for mouse.
I solved my concern.
In fact it is necessary to modify in the file advmame-1.4.rc the following line:
input_map [p2_lightgunx] mouse [2, x]
input_map [p2_lightguny] mouse [2, y]
Thank you in any case, I could not double cursor on any game.
@pickles I strongly suspect a faulty SD card. It's known that they get into a read-only state when they're approaching their end.
@jonnykesh No problem. It's just on a Rapsberry Pi 3b with Retropie 4.3. Had the same issue on 4.2.