I've been grooming fur on a model for a bit now and for some reason my ‘paint_furlength’ node won't display the brush overlay and let me paint. Well actually, it seems to pop on briefly in certain areas of the geometry then off again. Other paint nodes, before and after in the shop chain display and work fine. I've tried resetting the parameters in the interface, but to no avail. As a last resort I used the gear menu's revert to defaults and the brush comes back, but of course I loose all the paint work I've been doing. Is there some trick to jiggle this node back to a working state without loosing my painted values?

the painted values are on the geometry - not stored in the paint SOP…
just put another paint sop down after it…
maybe branch off a node from the bad paint sop and lock it for backup…

Okay, not a bad idea. I'll go ahead slap down another paint node as a work around. Or maybe even go back to a previous version.

What's strange is the paint overlay only shows up on one of the faces in the model but disappears for others. It seems the sop thinks this one face is the only valid face to paint on… oh well thanks for the reply.

is there anything in the Group parameter?