Instructions for the CF Zool2 "wheel":
Each numbered graphic is bisected horizontally with upper and lower half.
Match top half with game screen. T = Purple number
Match bottom half with game screen. B = Purple number
If T>=B then O=T-B
Otherwise O=T+10-B
Match "W"indow and "O" value and type in "A"nswer from chart.
Tested on a couple of Zool2 IPFs.