MegunoLink

I wrote some code for an Arduino board that lets me set and read back various variables using the MegunoLink interface. This works fine. However when I put the code inside a While loop I can no longer either set or read these variables, even when I modify the code so that the While end condition never occurs. Does this make sense? Any suggestions for a way around the problem while still using While, or an alternate approach that has the same functionality?
Any suggestions are appreciated.

Can you post your code and I'll see if I can help.

Cheers
Phil