Other than the fact that neither the new SRAM XX centerlock rotors nor Mavic SLR hubs come with lockrings:

1. Is there a compatibility issue? Spacers needed?

2. Where to find the lockring tool that is the right size to fit.
3. Where to find a 15mm front lockring in the aftermarket? Rear uses a cassette lockring.
4. Has anyone got this working for them?