If it gets powdery it seems like the product it drying out which, IMO isn't good. I usually use one pad for a whole detail and most of the time it gets built up with product so I take a terry cloth towel and wipe as much off as I can.
Take a look at this site, a member from another forum, blkyukon took pictures of the break down stages of SSR2.5 and how much you should use.... a great tool:
Polish Breakdown SSR2.5
Hopefully all of this will steer you back in the right direction to great results.
