[Closed] Render effect label problem

When adding my render effect to the render effect list I want a label in a rollout to
display the name of a material in the medit.

I can access the label and the label (dummy-) text from the plugin`s create handler, but it seem to be impossible to update it from there.

Why on earth doesnt this work ??

Also, is there a way to assign a variable as the label text in the rollout def ?