CVO and PAL - How?

Are you trying to do a true composite PAL signal? For that you need more than a simple video DAC. Or are you just trying to do an RGB or YPbPr component output at 576i?

In either case, your timings seem a bit off. For a 576i signal with a pixel clock of 13.5 MHz, the usual total frame size is usually 864x625 (864 * 625 * 25 = 13.5M).

One thing to check is if your DAC supports a pixel clock as low as 13.5 MHz. I have seen video encoders which require at least 27 MHz.