There are four steps to the Forgery Detection Training : the x-ray, the magnifier, the photo fake, and the paint analysis chemical tests.
X-RAY - Pass the wand over all 5 paintings and then select the one that has drawing underneath.
MAGNIFIER - Look at the three signatures (bottom right on each painting).
PHOTO FAKE - Click on the Moon. You should not see stars through the dark part.
CHEMICAL TESTS - After you put each paint sample in the liquid, watch the timer bar. As it reaches each of the four squares on the timer, the box will change color. Click on the beaker that is that color.
Test 1 : Green, Red, Blue, Red
Test 2 : Red, Green, Blue, Blue
Test 3 : Blue, Red, Blue, Green
You get it when you pass the Forgery Detection training with the assistant curator.
You have to re do it. It is not that bad.
Supply Room KeyYou get it when you pass the Forgery Training and are hired by the museum.Key to the Inspector's HouseYou don't have to find it. When you need it, it will be given to you.
Once you pass the test by the assistant curator, and finish the Forgery training, he will give you a key to the Supply Room.
Once you pass the test by the assistant curator, and complete the Forgery Training, you are hired and receive a key to the Supply Room.
After you have taken the Underground Tour, the security guard has an additional response in the Museum -- you can now apply for a job there. Pass the painting classification test (move the wrong paintings clockwise into the correct genres) and then take the Forgery Training with the assistant curator. This is how you get the key to the Supply Room.
Pass the assistant curator's test on painting styles. (see related question)
Apply for the job with the assistant curator and when you pass the Forgery Detection class, he will give you a key to the Supply Room.
Once you put the paintings in the right places (just move them clockwise to the right wings), you need to take the Forgery Detection training. Once you pass that, you get the key to the Supply Room and you can get the last Dragon Face picture piece.
Once you have taken the Underground Tour, you can apply for the job in the museum. After you pass the Forgery Detection class, you get the key to the Supply Room.
The keys on Counterfeit Island :The Supply Room - pass the forgery test trainingThe Inspector cottage - from the lady curator (late in the game)The dragon face lock - collect the six picture piecesThe Black Widow's door - you get the key card in the chase
The keys on Counterfeit Island :The Supply Room - pass the forgery test trainingThe Inspector cottage - from the lady curator (late in the game)The dragon face lock - collect the six picture piecesThe Black Widow's door - you get the key card in the chase