Thank you very much!  I myself have played it many hundreds of times, but I by no means always win.  That I still can bear playing it at all anymore, I think, means there's something good about it.

It does, I've not been able to get the OpenGL version to run beyond the title screen. One issue might be, perhaps, that my laptop has two video cards? An integrated one for battery life and a discrete one for when more muscle is needed.

Alas, on my system (Win10 64-bit) the OpenGL version crashes upon starting a game (selecting that option from the menu). The 7DRL version works though.