[Closed] delaying render effect

Is it possible to delay a render effect AFTER the render elements are created ?

I need in fact the shadow element in my scripted render effect, but as the effect occurs before the element are created the variable which will contain the shadow bitmap is still undefined.

Another question, but related to this one : is it possible to trigger the update button of the render effect window via maxscript ? As a nasty trick for now, i can in fact, via a mcr render the scene with its shadow element, add the scripted effect after the rendering… but i need to manually update the effect.

Thanks