Never had this problem with older iterations of zbrush, but now anytime I try to use curves( even if I turn on snap to surface ) they just don’t work. At default with snap turned on they dig into surface and veer off from surface when drawn. Never had to do anything special before, just turn on snap, adjust depth if need be and go so I’m not sure what the problem is now?
EDIT: Disregard. Was using wrong brush for awhile now.