Just to clarifly the buttons and switchs...
Reset (bottom Left) - Resets both timers to 00-00
Input Allower (Above Reset) - Allowers pulses into the circuit
Pulse (About Input Allower) - Pulses the timer which changes the amount of seconds you want to play with
Switch above Pulse should be active when selecting the time but off when not selecting
Switch above that swaps between players so you can select a differnet amount of time on each side.
Timer ON - Starts the 555 timer pulses onto the 7 segment displays
Swap Players - Once a player finishs there turn they switch the switch which starts the oppenents timer and stops there, so on and so forth.
Up/Down. - When selecting or playing you are able to change the direction on the number e.g. 1,2,3,4 (Switch) 3,2,1,0
Thanks