Screen Flashes Between Black and light grey?

I agreee with Wolron in that the main loop type doesn't usually matter. It does matter sometimes though, as a Repeat - Until will always go once whereas a While - Wend can sometimes never go if the While clause is not met. Goto loops are non-standard but do work. I also wonder if anyone has ever made a For - Next loop and adjusted the main For variable so that it never reaches the end of the loop.

Wolron: Problem with his code is that if he doesn't use flip, the user'll see nothing!