Toyota Repair: 92 toyota, piston rings, cylinder walls

Question
help v6 camery 3.0 overheated cranks will not start, replaced timming belt, water pump, tentioner and pullies, still cranks does not start. 3 pistons have no psi,  # 2 has 60 psi.  what can i do?

Answer
When the engine overheated did it stop running? What was the reason for replacing the timing belt? There are two p[ossibilities for this, either the timing belt is not put on correctly and it's out of time or the engine overheated to such an extend that the cylinder walls and piston rings were damaged causing the loss of compression. What I need to know is if the engine ran normally after it overheated and why the belt was replaced.