Argh! Now it creates a meanie but then it immediately disappears.
Hmm, the only thing I can think of with the code supplied is that your frame rate might be rediculously high and the meanie is moved off-screen by your position updating code before you get a chance to see it? Throw a Stop in your render_meanies() function and step through it, watching to make sure your values of \x and \y are reasonable. Or, if you need to wait until one's created first:
if keydown(88) then stop ; debug on <f12>
EDIT: Flip() is supposed to do a vwait, so that's probably not it after all...