[PyMOL] Color changes during a morph

[Max N. <mn...@em...>]

Hi All,
Can anyone tell me how I might change the colors of a specific 
selection during the course of a rigimol generated morph?  I would like 
one domain to go from purple to green, and have so far been unable to 
figure out how to do it.  I tried coloring the different start/final 
states before rigimol-ing but that did not work.  I have also tried to 
script the state coloring, as described 
here:http://www.pymolwiki.org/index.php/Color#Color_States_Individually. 
The problem is that cmd.set("surface_color", "newcolor", "resi 
430:572", a) for example, where a is the state, does not seem to work at 
all.  i.e. the color is not changed.  The idea was to change the colors 
as follows:

states = 30
for a in range(0,states):
     incr = 1.0/(states-1)
     r = 1.0-a*incr
     g = a*incr
     b = 1.0-a*incr
     col = "["+str(r)+","+str(g)+","+str(b)+"]"
     cmd.set_color("newcolor",col)
     print "COL state "+str(a+1)+": "+col
     cmd.set("surface_color", "newcolor", "resi 430:572", a)
     cmd.set("sphere_color","newcolor", "resi 430:572", a)
     cmd.recolor()

ugly, I know!  this is 64 bit pymol 1.5.0.6 eval for linux.  Thanks in 
advance,

Max