Hey, its my auction. But, ill tell ya how to do it anyway.
What i do for my cubes, is start with a new, old, cube. it really doesnt matter, as long as it is official. 1st, i sand down inner corners on the edge pieces ONLY. then, i clean it out. Next, i spray Silicon lubricant (called superlube. get it from a hardware store) into it. rotate it for a minute or two, then let sit for about 2 hours. now, lubricate again. sit overnight. Next day, wipe off bottom, and play with it. it might drip a bit on your hands for a few minutes, but its worth it.
p.s. After lubrication, let it sit on a paper towl, napkin, or anything that you can throw out.