Originally Posted by
Greenfieldja
With regard to buying the component group you linked to:
"What do I need to make it play nicely with Campagnolo parts?"
If you are going to buy the Campy group like you mentioned then that will come with everything you need to make this "play nicely" with Campagnolo parts except your rear hub. To make this work you would need to find a cassette that uses shimano/sram splines but has campagnolo spacing or you will need to change the freehub body if possible to a campy compatible one.
Or use a Shiftmate so the Campy shifter works either a Campy RD at Shimano spacing, or if it's just the Ergos you want, you can get a Shiftmate to run a Shimano RD with em. IMO this is a smart move because Shimano-compatible cassettes are far easier to come by, in greater variety. And also because Campy uses a wider cog spacing, creating more dish in the wheel.