Tim,
Are you starting 3DS with "3DS" or "3DSHELL" ? The 3dshell program is designed
specifically for times that you are shelling out of the program. Look on page
3-51 and 3-52 in the R2 manuals for more information.
-Brian
P.S. You might also be able to set environment variable or get more space using
the SHROOM utility (SHROOM.ZIP). Be sure to look on the ACAD forum, it might
have a more current version than the one in our libraries.
-Brian