I have a design based around a PPC. The problem I have is that I would like to change the default setting for XST when running platgen. Platgen will generate a default synthesis project file which in my case I would like to change. To be specific I don't want XST to use SRL rather I would like to have Flip-Flops instead. In this way I assume that it will mitigate timing, it can place the Flip-Flops apart rather than "having them" all in one component (SRL). Is it possible to change the default? Has any body come across a similar problem?