I am installing a DSC PC1832 in my home. I have four 4-wire leads for five Smoke Detectors. Can I place all four common leads with two each on the PGM1 & PGM2 terminals?

I am confused on " Four 4-wire leads for 5 smokes". You should be able to place all 5 on the High Current PGM.
The PGM connection allows momentary disconnection of power to reset the Smokes.