Ikea Kitchen Rail, What screws to use?

Hi there,

I'm installing an ikea kitchen, having had all of our service modified to fit with out service voids, and plan on using the rail system to hang units to the wall.

I have block walls with plaster/render and wanted to know what screws/fixings to use.

The instructions say to use non counter sunk screws, so pan head or flanged however i'm not sure what size is suitable, and if they work with standard Rawlplugs or not.

Anyone had any experience with these?

Best Wishes

Conoral11