As of this date, the book in PoK still works to advance your lockpicking. It's the rotating book on a table as you zone into Planes of Tranquility. You can buy the lockpick in the eastern chamber from the iksar. Hold the lockpick on your cursor then go to town clicking that book!
On the Mangler progression server (no PoT book yet), I'm able to get skill-ups from the jail cell doors in Najena outside of Rathyl's room. I wasn't having much success in other places (Befallen doors and rock outside of Paineel), so I put some points in via the guildmaster training prior to trying Najena. Maybe I needed a point to 'prime the pump' on the skill? I'm not sure if that's a thing.
Well, tonight I hit the PoT book to skill up my rogue gimp, she is level 63 right now. It took me all the way to her current skill cap of 292 for pick lock. It really didn't slow down very much either. From 150 to 290 took me maybe 20 minutes of frantic clicking.
By far easiest way is to invest some training points, buy lockpicks and then use that rotating book in PoTranquility. It's on the table to the left as soon as u zone in, My rogue went from 56 to 194, in 5 minutes. You do need a minimum skill level though to see skillups. I was told it was 56 so I spent training points to that but others have said as low as 40.
Looks like this maxes out at 194, which isn't bad. At least my 63 rogue stopped getting skillups at 194.
If you are high enough to go into PoT lockpick the book on the table right when you enter the zone - You will get to over 200 skill lockpicking in a relatively short time - You can do this at any lvl skill -
You only need one Lockpick - I was under the impression that you needed more - Unless it's like a fishing pole and breaks later . I only used one it worked from 0 to + 200 skill .
Ok I was just wondering how and the heck you actually use lockpicks to unlock a door. I have tried everything and the skills never go up and the doors never open.
To actually use your Lockpicks, put them on your cursor and click on the lock you want to pick. The only exception is LDoN chests. For those, you have to use your "Pick Lock" skill hotkey. You can't use the hotkey outside LDoN, and you can't use the picks on the cursor inside LDoN. They're almost like two separate systems.
Raising your Pick Lock skill is almost completely backwards from getting skillups in a tradeskill. In a tradeskill, you can't get skillups from items at or below your current level (trivial). You have to do something above your level to raise it.
You can only pick locks that are at or below your current level. You can only get skillups on successful picks. In other words, if you find a lock that you can't pick, forget about it. You can't open it and you can't get skillups on it.
I haven't personally verified this 100% yet, but there's also a bug with the Pick Lock skill system. You get the skill at 6. When you train your first point in it, you will have a skill of 6. However, the lowest skill lock in the game is 11. You can't get any skillups on any locks until you train enough points to get your skill to 11, so that you can pick a lock. The part I haven't verified is that there are no locks lower than 11 skill, which you could use for skillups instead of using training points.
The doors in Befallen are 11 skill. Once you've trained up to 11, you can max your skill on that door (or any other lock that you are high enough to pick) because they never trivial out.