My responses:
There is a secret place to stay before you arrive in Eunate, just a short distance. PM me if you'd like to know about it.
You can get silk liners on ebay.
I've never seen compeed until spain, but it is in every farmacia along the Way. About 6 euros per package with various sizes. I'd advise you buy some different sizes, and also some gel tubes for putting around toes to keep them from rubbing together in the beginning days.
I didn't use electrolytes... just plain spain water, which is excellent!
Keyboards are confusing for the first day or two, but not impossible. Just go for it... you'll figure it out.
I love the Travel Center, and found the folks running it to be especially helpful and inexpensive.
Leon and Burgos are both worth a day of sightseeing. Don't hesitate to visit any churches along the Way.. they are full of exquisite art, even those that appear to be nondescript. Take your time and see all you can. Don't bypass O-Cebreiro, although it's a tourist trap, it is beautiful! I also loved San Anton and be sure to stop for any fiestas along the way!
I personally would bus into Burgos next time and even into Leon... I didn't care for the industrial walking.
A lock on your pack wouldn't be offensive, but you might find it annoying yourself. Just don't take anything you can't afford to lose and relax! Leave the expensive stuff at home...
Not usually lockers. Put your passport, money, credit cards in a ziplock plastic bag and KEEP THEM IN YOUR MONEY BELT AROUND YOUR WAIST AT ALL TIMES.. Do NOT leave them with fellow pilgrims. Do NOT leave them in your pack. Do NOT put them on the bench outside the shower. Take them in with you. Have them in plain view AT ALL TIMES. Unfortunately, the very few thieves you will meet ARE there taking advantage, so use your street smarts and don't be too trusting. Sad, but true.
Never heard of anyone being mugged. But that said, don't be silly. Act as you would in any large city, avoiding dark alleys, etc. When you use an ATM, cover the keypad when you punch in the numbers.
BE SURE TO CALL your bank and tell them you will be in Europe or they could hold your funds, thinking your card was stolen. This has happened to more than one pilgrim!
Please carry a hankerchief to use when peeing along the trail. You can wash it out each night when you wash your laundry. Please do NOT leave toilet paper along the Way ... it is a disgusting thing for others to encounter.
I am one of those Americans with no medical insurance. I had no problems getting free or inexpensive help from local clinics set up to help pilgrims. For minor health problems (cold, flu, stomach upset) you can simply talk to the pharmacists, who are licensed to prescribe medication without seeing a doctor. Best cold/flu med I ever used was given to me in Santiago!
Have a wonderful Camino!