The zener diod in the right bottom of the schematics is actually used as a voltage stabilizer. Those points should be linked.

The "amplifier symbol" is just a ground symbol. Connect all those points as well.

If you have a PIC programmer, the programming of the PIC is not a problem. Building such a programmer is not that hard, search the net for a suitable one.

The plug you need for your buddy box depends on your transmitter manifacturer, but they are usually quite easy to find. Bring your transmitter to your local electronics store and they can probably help you.