I think it would work fine , if you had a powder with NO gravitational value, so it would just float around, that attracted OTHER particles then it would create little balls of powders
and if they all had a small gravitational field then they would start to join together, then you have small "planets" XD
only problem i see with it is if the gravitational map was to slow for it.......but GBMB seems to work just fine so in theory itll work