Using lowest setting will basicly only show you in witch direction shadow will be and how far it will go.
With big ugly dark squares on ground.
Terrain graphic are saved by it self and shadow graphic by it self.
You can lift this files out square by square and handpaint them in Photoshop if you like.
This is also possible to do with shadow files.
They are saved as targa.
When merging, you blend two files and
org files will still be untouched.
Without merging you can't see how nice it looks.
Not to worry. Everything looks ok.

If you like to look at org files, just delete the newly merged file in it's folder. Tada!
Making shadows are a time consuming thing (BF1942), more computers = more shadows faster.
BFV fix it all in one hour and without problem.Good luck.