Re: Drains of Doom? Check out these spells
From the FAQ:
"Q: The rules state that a Continuing Charge in a Power Framework remains in effect even if the character switches the Framework to another power. Is there any limit to this duration, or could a character with a Framework establish several powers with lengthy durations (say, 1 Day)?
A: There’s no limit under the rules, but obviously the GM should monitor this sort of power construct for abusiveness. The intent of the rule is to allow interesting and logical powers (such as smoke grenades in a Multipower of weapons), not to provide characters with huge amounts of power cheaply."
So it is rules-legal to switch slots and keep the Continuing Charge going. As a GM, I'd rule it abusive and disallow it; use Force Field instead.