Hi Sabuj, If I understand correctly you display GRASP surfaces in Chimera using the DelphiViewer extension and color them using an electrostatic potential. You are right that that information is not saved in Chimera sessions. Unfortunately many Chimera extensions do not save what they do when you save a session. Two ways of adding the GRASP session saving you want are possible but both require significant work for us to implement. It would help to know which method would be best for you. Then we can put it on our requested features list and evaluate how hard it is and what priority it has relative to other new features. The first method is for the DelphiViewer to remember all it's settings and surfaces it made. It would remember the potential files you used, the GRASP surface files and the thresholds and colors you set. Then when reloading a session it would reread those files and recalculate the colors for the surface. The other approach is that sessions would just remember the colored surface directly but would not remember how DelphiViewer created it. You wouldn't need to have the potential file around, but you also wouldn't get back the threshold and color settings you originally used. Thanks for reporting the color editor opacity bug. It will go into our bug database and should be fixed in the next release. If you can't find a bigger bug than that (not counting missing features) then we are doing pretty good. Tom