I want a ARSecretWall01 to open when some special items are added to the right containers. BUT IT DOES NOT OPEN! There are six items and six containers. Only when all items is in the right container the secret wall should open. I've made a script to each item and a quest script.
Here is how the items' script looks like:

scn PuzzleItemScript ; it's not the same script which is attached to all items ; this is an exampleshort AddedBegin OnAdd PuzzleContainerRef ; 1/6 set Added to 1EndBegin OnAdd Player If ( Added == 1 )  set Added to 0 endifEnd

And here is the quest script:

scn PuzzleQuestScriptshort OpenBegin GameMode If ( PuzzleItem01.Added == 1 ) && ( PuzzleItem02.Added == 1 ) && ( PuzzleItem03.Added == 1 ) && ( PuzzleItem04.Added == 1 ) && ( PuzzleItem05.Added == 1 ) && ( PuzzleItem06.Added == 1 )  If ( Open == 0 )    PuzzleSecretDoorRef.activate    set Open to 1  endif endifEnd

If anyone can tell me what I've done wrong I would be grateful.

Maybe try PuzzleSecretDoorRef.PlayGroup forward 1 ?

I'd suggest checking the variables for the script on the door. There may be a reset timer that hasn't expired or something like that preventing its use.