In this screenshot the player recently set depth to 92 feet (see message window) while he is currently at 113 feet:
http://www.subsim.com/sh4/sh4_mp4.jpg
Being able to click in dials to set speed course or depth is pretty basic (was in SH3). Afaik you don't need mods for that. Mods may change color of the needle but I think it's default. Unless it was one of the bugs still left in the game that I forgot about.