Some of the touchier colors like reds and yellows "cook" and bubble really easily - is this 104 coe? Doesnt really matter, boro will do the same. It doesnt even take much heat to get them to bubble and roughen. Everyone always says work further back in the flame. I have found , that means, moving your glass further away from the torch head not a couple of inches, but for me, like 8 - 10 inches.... Just a couple inches never works for me- and then there's the whole patience thing with working further back. Also once the glass has devitrified and roughened from too much heat, some of that doesnt re-work back out very well, even in slow low heat. Perfect example is take a yellow and then bubble the heck out of it, right on the rod so that it devits, then try to fix and work back out - some of the bubble spots that have overheated and turned white so that it looks like coral wont blend out.
But like menty said if it looks wrinkly instead of the texture of coral, then its more than likely, devit from low heat because the surface of the glass has cooled before the inside while its still moving, rather than devit due to overheating. In that case, check your surroundings for drafts, room temp, etc. if your ventilation is really aggressive, it's possible its cooling the outside of the glass too fast.
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