SSP includes the mouselook mod, shlink ditto.

Neither. That is a mod which is already included in SSP.
If you are playing SSP, just tap 'e' to enter mousemode. Tap it again for use mode.

just download SSP, enable the mouselook mod and you are done. hit E ingame to switch between use mode and shoot mode, almost SS2 style. the odd thing is that you will have to enable the use mode every time you want to interact with something, but you'll get used to it fast enough.

It didn't use to be like that, before St. Malba came upon us. Blessed be his name.

I managed to learn how it works in an instant and already played around a bit. I'm in for some adventure I feel.
What's the difference between standard DOSBox version and Gulikoza's DOSBox?

Yah, but then gulikoza's build was created a few years back. The dosbox main build has been updated since. So I don't expect gulikoza's to yield significant advantages any more. Of course that might all depend on the host system, so try it and see what works better for you.

anything higher than 640*480 is a hack, completely unsupported, and may, or may not work properly.

System Shock Portable is superb, freeing us from the worries and troubles of trying to get a (notoriously difficult to run) DOS game working fine on modern PCs, and it goes the extra mile by really making the game effortlessly playable to those of us who are so used to the WASD + mouse style controls that we have difficulty using SS's usual control scheme.

Thanks so much to everyone involved in making SSP, it really is a fantastic package.