How low is the battery?
How do you know the clutch switch is working?
One of the signs it is not working is when the key is turned to start the engine the dash lights come on but the engine does not crank. There is a technique to bypassing the switch but I can't recall it from memory. But it might be worth searching for and trying.
The RFID in the key you are using might have died. (The security system in this would register an error code and with a Porsche diagnostic computer or a Durametric (I believe) error codes can be obtained from the security system.) In the meantime have you tried another key?
In replacing the system the electrical connections may not be good, could have worked loose. Or you damaged the antenna that the security system uses to communicate with the RFID pill in the key.
For the clutch switch, replace (it doesn't cost that much), or bypass, Or you can work the clutch pedal vigorously then press it down all the way to the floor and try to start the engine. Do this several times. The switch can stick or the clutch pedal linkage can develop wear and play and the clutch pedal arm may not make full contact with the switch plunger.
With the ignition switch you can work the key/wiggle the key, apply pressure radially as you turn the key to try to start the engine to see if it is just a marginal contact. If one of the wiring connections is bad this likely won't have any affect. It won't have any effect if the antenna connection is bad.