Thanks for the tip, Les - My problem was when I saved the lightset or saved the pz3 the lights would revert when reloaded. I tried it again and found it worked if I did a Edit>Memorize>Lights before saving the light set or pz3. Now the limits seem to hold the 180 setting. I also discovered that the black shadow on the ground plane that some are getting can be cured by backing off one of the two lights by a trans of -0.001 (I did a zTrans) so that the "barn doors" are almost touching but not quite.