Diesels take a long time to warm up because the pump air wide open, no throttle blades restricting flow, especially in winter and if you are using cabin heat. You will see cross country truckers with canvas covers over their radiators in winter to keep engine/ coolant temperatures up. 185- 190 F sounds fine especially for December. I replaced three thermostats in my first couple of years of ownership before I figured that out.
The only way to be sure about timing is to go to a diesel shop that has a timing device for diesels.
On the cold knock question, does the engine exhibit typical cold knock or rattle then quiet down after the cold timing advance solenoid trips off? see the post below, some things to check. If the cold advance does not trip off the engine will be noisy.
For whatever it is worth, the sounds on your tape seem typical to me and I have run my truck 125,000 of the 267,000 on it, both NA and with the Banks turbo, and two different engines.
But get the timing accurately measured and set with a proper instrument and confirm that the cold idle solenoid is working.