hmm i guess there's no going around it :( thanks for the response! i'll give what gamedev said a try, although i don't quite understand what you he meant about "saving out my canvas w/ an alpha and using that as a texture". does that mean render it out as a png with nothing in the background?
You can actually also use the grass meshes as well. You would create your FX and then go to Modify-Convert-PaintFX to Polygons or something similar. Since it still uses a shader you would have a shader slot already created in an engine like UDK, you'd just have to play with the second UV channel for lightmaps. The problem…