Unfortunately, I know nothing about modding.
Fortunately, I'm willing to learn.

Anything I should know right off the bat?

Read the documentation located in BF2_Modtools\documentation\

go to the everything you need thread, it has everything you need http://www.gametoast.com/forums/viewtop ... 27&t=13806

Modtools download: http://starwarsbattlefront.filefront.co ... s_PC;57352
Install those, the default directory is C:/BF2_Modtools.
If you'd to install them elsewhere, make sure the directory has no spaces in the folder name.
For Example, "BF2_Mod Stuff" won't work, but "BF2_Mod_Stuff" will
READ THE DOCUMENTATION (found in C:/BF2_Modtools/documentation) THOROUGHLY, starting with the Getting Started doc, which will give you many of the basics you need to creating your first map.

Some other programs you may find useful:
GIMP: Image editing program. Used by modders for skinning units.
Notepad++: Text editor (like wordpad, but a lot better)
XSI Modtool: Free 3d Modeling Program you can use to create your own objects

After you've followed that, explore the assets.
Most of the files in the assets (except for a few) can be opened with either wordpad or Photoshop/GIMP.
Some different kinds of folders you may encounter in exploring the assets and what are in them:

odf - Contains the .odf (Object Definition File) files.
These essentially define the objects, what they are (prop, vehicle, infantry, cp, destructable building, etc), what they do, and what model/geometry they use.
Opens with wordpad.

msh - Contains the .msh (mesh, or model) and .tga (textures for the models) files.
Basically, the odf calls for a mesh in this folder, and the .msh file calls for a .tga texture to use on the model.
.msh kinda opens with Wordpad, fully with hex editor. TGA's open with Photoshop or GIMP.

req - These contain the .req (required) files.
Every unit, vehicle, and turret needs one of these. The whole side also needs one.
Read the Jedi Creation Doc for more information.
Opens with wordpad.

effects - Contains the .fx files and some textures.
.fx files are basically effects, such as explosions, fire, or rocket trail effects.
Opens with wordpad.

After you've got the basics down (adding objects, messing around with terrain, etc.), you may run into some more specific problems.


What to do when a problem isn't covered by the docs:

1) Use the search function. Absolutely the first thing you should do, it is super-helpful in finding topics about your problem deep within the depths of Gametoast
2) Check the Modding FAQ, found here: http://www.gametoast.com/forums/viewtop ... =27&t=3497 This Everything You Need To Know thread will also have some revamped and easier-to-understand versions of some documentation, so if in doubt, look here.
3) Post a topic in the modding forum How does one do this, you may ask?
-Briefly describe your problem, what you did, what happens (specifically, not just "it crashes"), and post your error log.
-People will often ask for an "error log". This is a log of errors (duh) that a program called BF2_Modtools.exe produces.
Go to your C:/BF2_Modtools directory, and copy the BF2_Modtools.exe
Place it in your Program Files/StarWarsBattlefrontII/Gamedata folder.
Run it. A windowed version of SWBF2 should pop up. Play your map, then close out of the program.
Go to Program Files/StarWarsBattlefrontII/Gamedata
Open up Bfront.txt, and post the log in your topic.
-If, after munging, a MungeLog pops up with ERROR messages, then post those too. However, WARNING messages can most often be ignored.

Two other useful programs are Particle Editor (to make custom lights/explosions, etc.) and Hex Editor XVI-32 (to hex-edit, although I've heard that there are better ones). Also, check out my PM.