Re: Random pixel shift to the left
First, have you verified the hold/setup/strobe times on a scope? Is there much jitter on the pixel-clock with respect to the h/v sync and DE? Do you have flexibility to slow down the pixel clock to see if that affects it? You can change the clock by changing the divisor for PBCLK8, I believe.
Opinions are my own. Everything I describe is very likely wrong. Use at your own risk.