Hi,
thanks for report. Primary testing device for Magic Dosbox is Nvidia Shield Tablet. So, I hope I will be able help.
To your first question. The black cursor is shown if you connect bluetooth mouse or pair tablet with shield wireless controller. Unfortunately the black cursor is annoying and is not able to remove it 🙁 This is android limitation and question must be directed to Nvidia – only they can make special option for that.
Nvidia Shield Tablet has troubles with bluetooth mouse – tablet translates wrongly some information.
I posted the problem here, but nvidia is ignoring it :
https://devtalk.nvidia.com/default/topic/815807/android-development/physical-mouse-bug/
I have idea for workaround, but I can do it to version 30. Currently is going out version 29 and is in latest phase. After I release the version 29 (in next 4-5days) then I will look at this problem.
Sorry, probably I will not make you happy today:(
Tony