Thanks! you can change the mouse sensitivity in game.cfg (it will be created automatically first time you run the game). The option is called “mousespeed” and takes a value from 0 to 99. It’s under the “controls” section. I intended to make an in-game settings screen for all this, but couldn’t make it in time.
edit: optimus just pointed out that this won’t work. the reason is a stupid rename bug… the game looks for control settings under “ctl” not under “controls”, so it won’t find the values you put there. Rename the section to “ctl” and it will work, but unfortunately it will also over-write the config file with the wrong name again on exit, so save a backup :)
edit2: or better yet, just run this patch I prepared, which patches the windows executable and fixes the issue. run it in the same directory as the game executable, delete your game.cfg and start the game again to re-create it with the correct “ctl” section, then edit the mouse sensitivity and it will work: http://nuclear.mutantstargoat.com/sw/games/deeprunner/releases/deeprunner_patch1-win32.zip