I dont know if I can offer that much help, since I haven’t used Torque yet (will be though next year if all goes to plan) and I’m not sure if your question is more to do with the actual implementation or the theory behind it- but the approach I would take in theory to doing a night scene in the likes of OpenGL (possibly a naive one too) would be something like this:
Do a rendering pass with one big light (a point light) overhead the entire outdoor scene in order to simulate the moonlight. Also add in a certain amount of ambient light to get rid of the total darkness and to fake the light bouncing off of surfaces. Adjust the colors and intensities of the moonlight and ambient light until you are happy with the result. Shadows would also play a very important part the effect.. Seeing moonlight make its way in between gaps of trees in a forest would be a very cool and atmospheric effect indeed..
Then for each additional light (say for your torch lights and such) do an extra rendering pass with the scene lit only by the light source in question and combine it with the first pass we done. Again shadows would be nice.
Now this is slightly simplified (shadows do not take 1 pass) and how you’d translate such an approach to torque I don’t know! But be sure to drop by at gamedev.net as well, there are plenty of smart folks on those forums who may have already used the engine and who might be able to offer more help.
Good luck anyhow.