the winny i have is a very soft and white powder, its similar to flour. it should melt at about 450-470 f. oven temps vary ALOT. my winny turned carmel color and melted at about 400 f. i used 2 diff oven thermometers, so i think it was somewhat accurate, but i wouldnt be suprised if my readings were 20-30degrees off. when the oven cycles on the air temp rises faster than the thermometer reads.
so my powder prob wasnt pure, or it wouldnt have melted at such a low temp. but close enough i guess.
bass i think we had the same powder cards for winny, that might have been why you had such trouble getting it inot oil, cause of the purity.