They do both centrelock and 6 bolt with the adaptor.
They are the centre lock versioin, but have a 6 bolt adaptor so you put the rotor on the 6 bolt bit and then do the centre lock bit up and bingo. Easier than doing 6 bolts up. Centre lock is a far better system.
No idea about conversion. But looks like it... http://www.wheelbuilder.com/dt-swiss-axle-conversion-kits.html
They do both centrelock and 6 bolt with the adaptor.
They are the centre lock versioin, but have a 6 bolt adaptor so you put the rotor on the 6 bolt bit and then do the centre lock bit up and bingo. Easier than doing 6 bolts up. Centre lock is a far better system.