Did it function normally before you disassembled it?
If it's the curved linkage is it oriented correctly?
Strait or curved, is the spring in position on the linkage?
You might try mocking it up without the stock. You may need to put a spacer on the screw between the trigger plate and the saftey extension.
Without the wood, you should be able to watch as you articulate it back and forth and see that the linkage is able to go through its range of motion.