Rubbing Compound

[RJ 325is]

I bought a buffing/polishing wheel that attaches to a drill and it also came with the white rubbing compound bar. I noticed my drill does not spin quickly enough to melt the compound bar onto the buffing wheel. Would it be safe to heat up/microwave the compound bar for a few seconds so that it will be easier to apply onto the polishing wheel.

I'm currently trying to refinsh some BBS style 5's. Thanks