Co-pay-key, huh? How long do you need to live in Columbia County before you're allowed to use that pronunciation?
I never heard that one, but there are lots of localizations of names around here.
Milan, NY - a little south and west of Co-pay-key - eventually becomes "Milan(t)" after you live there long enough. I think it might need generations...
Newbies say Amenia "A-meen-i-a" but locals say Ameenya.
How about Halcott and Halcottsville out by Delaware County - I am trusting Flammeus that "Hawk-itt" is correct enough for the likes of me... but non-local hikers look very confused by this localism.
We all know about Kay-ro vs. Cairo, but what about Athens? I swear I was told its "Ay-thens" a few years back.
What is the right way to say Kanape? Re: the brook and trail up Ashokan High Point.
And forget about road names - it is a dead giveaway that you're not from around here if you use those newfangled route numbers. Roads are all about routes to old friends houses, past barns that burned down back in the sixties, after the new house (i.e. built in 1980) got built, etc etc. Flammeus is out in very rural areas in the western catskills, often looking for houses/people and getting the most wonderful stories/histories of the area when he asks for directions.
As far as ice climbing at Bash Bish - I've been there in deep winter, and the falls are amazing - like a gothic cathedral. I know nothing about ice climbing, so I have no idea whether or not it is legal or safe. It is a very accessible spot by car and foot, so it is quite heavily patrolled (especially holidays and summer weekends), and also well-used. The creek is lovely on both sides of the falls, but there aren't any other, more remote cascades in the immediate area.
The bike riding on the rail trail is really user friendly. I would recommend the section from the village of Millerton south for a few miles. Great views, and some nice rock cuts, brooks, a big farm with a pumpkin cannon just to the east of the rail trail (Daisi Hill Farm). Cannon and a catapult - should be shooting pumpkins like crazy that weekend!
Enjoy your visit!