No there is no negative level or umd requirement for any burst or blast effects. The only items effects that give a negative level clearly state so in there description. IE unholy - negative level to good aligned, netural will not suffer it. And holy - negative level to evil aligned (yea theres no evil playrs in the game yet, but maybe some day)
Tested and confirmed on them all, use dual holy pg burst/blast on my true neutral 0 umd barbarian all the time.
Re: Earthgrab - guildie has this and have tested it with him.. Like all red name imunities - they work as expected, there imune to all effecst that freedom of movement works against - so yes earthgrab too. Same for blindness - so radiance doesn't work either.
That said, yes all these effecst work on orange named and none seem to check for SR.