I had a wonderfully working Lupu-5.2.8, and when I upgraded the guest addition from 4.0.12 to 4.1.14 the problem of the mismatch between the mouse location and the cursor surfaced. Going back to 4.0.12 guest additions, even with 4.1.14 VirtualBox solved the problem. In Wary 5.2.1 going back to 4.0.1...

I have the same problem, but only with the 5.2 and higher. I suspect it has something to do with the new Xorg level.

Waiting for a solution too...