RHEM 2: The Cave uses a simple point and click interface, and plays from a first person perspective. There is a very small number of items to find and use. Cursors will indicate an action can occur, and directions you can turn. It utilises prerendered graphics, with little Quicktime animations throughout and the occasional video clip of a real person.

You can usually turn left or right from one spot, occasionally look up or down. It's a slide show effect, a la Myst, and whilst I would have liked some 180 degree panning in the turning huts room to help my orientation, and a little more peripheral vision in some corridors and shafts, it's a perfectly acceptable way to present an adventure game.

As I said earlier there is no soundtrack, but there is ambient sound which is all you need. The sound effects are quite well done; bang on things and hear an appropriate response, be it metal or wood. Like everything else, it may be to your benefit to pay attention to what you hear.
There are a limited number of save game slots (10), something about which I always wonder. I can see no earthly reason why a game should need to limit the number of times I want to save. You can't really do anything wrong here, or at least nothing you can't undo, so restoring earlier saves is unlikely. However, if you like to create save games at key images to examine them later if need be, then you will be tested here.
Curiously, the save game records the playing time elapsed, but it isn't cumulative. So each time you start, even if you play from a single saved point, it will only record the current playing time elapsed. I can't see why it would do that, unless it is to remind us that we have been playing for two hours and, perhaps, had better have a break.
There are instructions for a full install, which I did, and there was no lag, no disk swapping, and no glitches or bugs. Everything played as it should, but if it doesn't you can bet Knut will fix it if at all possible. His after sales service has always been top notch.