Here is a cheat for Inertia Software's Mini Golf Mayhem (the Eureka version). It uses the FPS display to show the exact angle and power, along with the target angle and power (or the last if no target has been set). In addition, Backspace can be used to undo the last shot.
Cheat (24k, with source).
My holes.txt file, if you're too lazy to find the target shots yourself. Not all tee positions on all holes have been found, and some targets are wrong (it seems the ball may sometimes move a little when it gets reset).
27 May, 2006.