ok...I can offer a couple of hints...
1) Look in strange places for clues/objects (like under the plastic chair
)
2) Try everything on everything....even the objects you have collected can be used on each other (batteries in the torch for example)
3) there are actually 3 wall panels and a safe behind the picture
btw - I am stuck on the last last last thing.....for 3 days
shout if you want any more hints..