I have created a spell with a constant effect. It uses ScriptEffectStart and ScriptEffectUpdate blocks to maintain the effect.

My question is, will the effect be cumulative? I mean by using a return statement in the ScriptEffectUpdate block, will the effect (resist normal weapons) be cumulative? It is a 5% effect, but will it grow to 10%, 15%, 20%, etc. every time the block runs?

Not for sure, but, just in case.... might want to check and see if the effect is active, and if it is, don't do anything.

Yeah, good idea.