Are the keyboard and mouse controls rebindable? Is mouse supported (for aiming and menus)? How does the game save progress? Checkpoints, auto-saves, quick-saves, etc.? Is melee viable? As dodging bullets and stabbing the foes?

I look forward to tinkering with it to run on my Anbernic RG353M; shouldn't be terribly difficult, the handheld is running ArkOS, a 64-bit Ubuntu 19.10 based distro, on a 'Rockchip' RK3566 board. Already has a long list of ports, including Doom, of course. ...