I still couldn't solve the problem. The Rotate tool does 90 degrees at a time witch is always too much. I did find that if I align the chip along the vertical axis of the scan bed it comes close - after 3 clicks on the rotate button. Here are a couple of my tries - close but no cigar. I guess I'll just have to keep using Gimp to fix the scans. Thanks for the help - at least I know what some of the buttons do