I use the same set up but only process one sheet at a time and have not had the problem you are experiencing. What I load the film in the tank do you make sure it is trapped behind the ridges and prevents the film sheet from movng?

I have not used Pyrocat in this setup but have used HC110, D76 (1:1) and XTOL with good even results. My procedure is very similar to yours.

- Mike