CstDoom3 is something of a mod-pack for Doom 3 and the expansion Resurrection of Evil with a bunch of minor unrelated alterations that seek to improve the gameplay experience, with all of them toggleable. If some features are to your liking while others aren't, you can just pick and choose which to turn on. The changes include adding RoE weapons to the vanilla campaign and vice versa, HUD indicators for stance, a headlamp, and a small pop-up that shows the access code associated with the given lock, provided you've found the document that shows it.
Credits: fva
