Does icy rock work with Chilly Reception? I would assume it does but want hard confirmation :)
Yes, it should. Chilly Reception still gives the Def Buff for Ice Types and still sets up snow as normal, and since Icy Rock is used to prolong snow, it will work as intended.
What does Tinkaton do, does it actually do something worthwhile?
It has one of the best typings in the game, and although it has lacklustre stats (for the most part) it comes with a pseudo-nuke move that enables it to hit a lot of top-tier threads surprisingly hard. Chien-Pao and Flutter Mane are OHKO'd by 252 / Adamant Gigaton Hammer. It also has a solid support movepool, it'll probably see more play in VGC than OU, but its movepool + typing + Gigaton Hammer will probably let it find a nice niche within OU once the metagame settles down.
I find it's fairly useful to check the contribution threads for the newer Pokémon to see what more experienced players are using to get a general idea; here