Now this is really strange, because my method should work under any circumstances.

My only guess is that there are some dependencies in your document that somehow went bonkers.

Make a backup of your file, delete ALL dependencies that you can get hold of (use Poser for this), save it and then try to apply the code lines that I've suggested above to your document (in PoseFileEditor if you have!).

One of the main problems with lights is that if they do have a preset value in the lights parameters themselves,you may get weird results with "valueOpDeltaAdd" if you don't calculate the "deltaAddDelta" correctly!

Even with "valueOpKey" it may become complicated if you don't set all keys (esp. min and max values to the correct values, and it even becomes harder because the curve from one key to the next is interpolated as a bezier curve ~~~ by the program, which may oveshoot or undershoot the correct values for any settings in between.

_In short, you're about to open a can of worms here! _

Especially if you don't eradicate all the other (probably wrong) dependencies that you already have in your document.

Karina