Tekapo High Country Trek

Googled this and got Gottlieb Braun-Elwart's company Alpine Recreation who run a circuit I'm guessing from Mt Gerald Station to Gottlieb's Hut, then onto the ridge that runs from the hut North-East along towards Stag Saddle, back to the hut probably via Camp Stream and then presumably north to Stone Hut Stream and down the hill to Stone Hut and back to the Lilybank Rd. However, you may be referring to that section of Te Araroa that runs from the Coal River over into Bush Stream via Camp Saddle. The Te Araroa site gives a time of 10 hours to do this stretch from the road end to Camp Hut and onto Royal Hut in Bush Stream. I've got plans to do a circuit involving this area sometime. Stag Saddle is the highest point along Te Araroa. I can see that what the company calls Snake Ridge would be fantastic for ski touring.

If it's the commercial trek then yes, most of it is 4WD road and the route along the Snake Range won't be marked but may be consolidated by foot passage. The route down from Stag Saddle via Camp Creek is part of Te Araroa and so will be marked with poles but possibly to a very rudimentary standard at times if the other side of the saddle is anything to go by.

I still couldn't work out which ridge is called the snack ridge exactly... I couldn't find it on any map but I think I'm not very good at looking for maps...

Yes, it's not marked on the map but it runs on the true right of Camp Stream from the peak by Stag Saddle.