Helen,
It's not possible, the only workaround I have found is to copy the WordArt
paste it back with paste special as an enhanced metafile *.emf, which allows
you to ungroup the SmartArt, then individually select the bullet boxes and
remove them. After that you can regroup. Off course that leaves you without
the original, so work on a copy.
Sure hope someone else has better suggestions for you.
Insert a text box with dummy text outside the SmartArt. Format this without
bullets. Use the yellow format painter brush to copy this format to the text
inside the SmartArt. Delet dummy text box.
