The Finger Contax 645 adapter is an interesting adapter. It requires the use of a Fujinon GF 63mm F2.8 R WR to activate the adapter, which only has to be done once. I hope this requirement can be worked around in the future, but also of interest AF is only ensured with the 35, 45, 80 and 140mm Contax 645 lenses. Hopefully, this adapter expands in usefulness going forward. I might order one for my GFX when preorders start. I love Contax glass and would love to gain AF access to their 645 lenses on my GFX. Adapters aren’t available at the moment, but when they are you will be able to order them here.
Update: Trying to clarify lens support with Fringer Zhao in our Fujifilm GFX Owners Group if you have questions.