You scale the model in your modeling program before you import it. I "truescale" my models. What that means is 1 scale unit in your modeling program like 3dsmax is 1 meter. If something needs to be 300 meters then i scale it in max to 300. Though i think lightwave is a better tool to scale with.

You can put the forge files anywhere except that the particle forge needs to be in your root sins folder. All others can be run from anywhere.

Where do I get that 3d modelling package

also Major stress said put it anywhere so I assume that I cannot acces the forge files from the main soase screen.

Actually, if you want to resize the game models, you need 3DSMax. The only way to get meshes into a 3D modelling package is via an unofficial script for 3DSMax (as far as I know). XSI mod tool is needed if you want to make new models, simply because its easier to use it to make .xsi format models ready for conversion than the aforementioned Max script.

Also, since it looks like you're totally new to modelling, keep this in mind - it takes a lot of time to learn how to use a modelling program effectively. I have years of modelling experience under my belt and I can tell you right off the bat that if you want to make stuff which looks even relatively good, be prepared to spend at least a few months simply learning what works and what does not. And not just 3D stuff either - a model also needs a good texture, so that's one more program to get acquainted with.

I don't mean to sound discouraging, just want to give you a heads up so that you know what you're "up against". Modelling can be and is *great* fun, but you've got to love it or else you will probably give up before you can acquire any modicum of skill.