Dragon Age Origins: Max Lockpicking skill, but still insufficient

Bump up your cunning stat a bit; lockpicking gives you a bonus to cunning for all lockpicking tasks, but maxing it out does NOT gurantee that you can open every door/chest.

Try adding some equipment that gives a bonus to cunning; that should work as well. I know some chests in my game refused to open until I got cunning to about 42 or so [though I had a LOT of +2 equipment equuipped by that point]

It may be that your cunning is to low. I have read threads that you can have the 3 rd level lock picking and a 30 cunning and pick anything in the game...

All lockpicking does is give a bonus to your base cunning score when attempting to pick a lock; in theory, a large enough cunning score doesn't even need the lockpicking ability at all.

In this case, the two chests I know of that you need higher then Level 4 lockpicking/the cunning needed to get the skills:
1: A chest on the next to top floor of the Circle Tower
2: The chest in the Redcliff General Store

Ironically, both contain junk; I understand random item placement, but how about at least matching the quality of items with chest difficulty?

This is copied from the Bioware forums:

This information comes from placeable_h.nss and GetDisableDeviceLevel() in core_h.nss.

Whenever you attempt to unlock a chest or door, the game calculates a lockpicking score (L) and compares it to the lock difficulty (D). If L >= D, the attempt is a success; otherwise it fails. Unlike stealing, there is no random element in lockpicking.

The lockpicking score is simple to compute:

L = (cunning - 10) + 10 * [lockpicking rank]

Your lockpicking rank is the number of points you have in the Deft Hands tree. If you have Deft Hands alone, your rank is 1; if you have Device Mastery, your rank is 4. As you can see, each point in the Deft Hands/lockpicking tree is worth 10 points of cunning. Notice that you can actually open locks without any points in the lockpicking tree if your cunning is high enough (I confirmed this in-game).

If you successfully pick a lock, you'll gain XP equal to D (with a minimum of 5). Thanks Sheffsteel for the observation.

Great! But how high does your lockpicking score have to be to pick every pickable lock in the game? Unfortunately I don't have the time or know-how to inspect every lock in the toolset to find a maximum value for D. However, there is a big hint in traps.xls, which contains a sheet called lock_difficulty with the following table:

1 Auto Success
10 Simple
20 Very Easy
30 Easy
40 Medium
50 Hard
60 Very Hard
10000 Impossible

So I would tentatively suggest that you need a lockpicking score of 60 to pick every lock that can be picked. You can achieve a lockpicking score of 60 by getting Device Mastery + 30 cunning, or Mech. Expertise + 40 cunning, etc. Of course, some locks will still require keys or event triggers to open.

Some people have finished the game with a lockpicking score of 60 and said this was enough to open everything. One person on the old forums said he was unable to open a chest with a lockpicking score of 64, but I don't know the circumstances. I would appreciate feedback from more people about whether 60 is enough for everything.