I think the original poster may have been asking about the new Zeiss glass, not the older Contax glass.
Looks like you're correct.
Have used the 35/2 and 100 ZF and while very sharp, etc., I found the new ZF line (save the 50/2 macro) not that strong re: CA control. Some of the longer units are also relatively large diameter lens barrels and with the small diamter Nikon F mount, the execution of their aperture controls (for a stop-down shooter) can be a PITA and cause focus shift as you inadvertently move focus ring stopping down post-focus. On a Nikon, it's a non-event.
Look at
www.pebbleplace.com re: the 50/2 ZF. Quickly stopping down takes skinny fingers. Doing it with gloves - would be 'interesting'. I also HIGHLY recommend Lloyd Chambers ZF line reviews and tests - worth the $$. A good source in US for ZF glass new and used is Tony Rose at
www.popflash.com
Nikon-EOS adapters are available from cameraquest/Kindai, happypagehk (ebay), Fotodiox, etc. Many, due to their design, do however have a tendency to allow some minor but ANNOYING rotational movement when focusing well-dampened lenses (which many ZF lenses are).
The problem comes from the spring-loaded locking pin/slot combination that many adapters (most being sourced from the same 3-4 Chinese manufacturers) use to secure/release the lens to the adapter and the combo to the mount. The slot in the tab is wider than the EOS locking pin which allows movement. The tab, being spring loaded also can tend to start to woble around over time, allowing a second order movement.
With my Hassy 110/2 I use two adapters - a Hassy-Nikon and a Hassy-R. Both are then used with chipped Nikon-EOS and R-EOS adapters custom coded for (in this case) 110MM F2. for some exif capture. The Nikon combo rotates a degree or so when you start to focus - not major but annoying - and makes minute focus changes a PITA. The R combo - rock solid as it's lock/release mechanics are different. Same adapter source- HappypageHK. I THINK Fotodiox's pro Nikon adapter (or is it's cameraquest/kindai?), not chipped, uses a better latching mechanism.
Again, see
www.pebbleplace.com. John's experience with the 50 and using a Nikon adapter with it mirror mine with the 35 and 100 ZF on my 1Ds2.
Great lenses, but using them on a Canon body does come with some foibles. Some units in the CZ YC and N lines, as well as Leica and Nikon Ai/S and non-G mount IMHO offer comparable performance in many cases for less $$ - and the chance at (for N units) AF conversion. Example - the IQ differences between the 100 ZF and Nikkor 105/2.5 doesn't justify the VAST price difference IMHO.
For a stop-down user, if the ZF line were APO corrected and more mechanically stop-down friendly, they would be worth every penny; but given they are not - there are equivalent lenses out there for less $$ that handle better (again on a Canon).