I've been lurking here for a long time learning and now find myself in DEEP trouble with my very first install!

Car: 99 Hyundai Elantra (no frills model)
Alarm: Viper 690xv Responder
Problem: No siren chirp, no LED, no response to valet switch, no alarm.
I don't know what I've done wrong! Planned it all out, got the manufacturer's electrical diagrams, got the wiring diagrams from here, and verified all wires before connection with my DVM. Had the battery disconnected during install and soldered all connections and made neat, hidden looms. When done, I reconnected the battery and then plugged in the 2 fuses for the brain. I was expecting a siren chirp, but nothing happened. I verified that the ground was solid and where I tapped for +12V constant was good - both were. However, I couldn't get back at the brain to verify everything there (dark and cold here now), and I tucked it up high in the dash.
Guess I was too smart for myself thinking everything would work!
Anyway, I thought maybe the brain wasn't getting power or was dead, but then I noticed the LED inside the shock sensor responded when jiggled, and the brain is also operating the domelight supervision relay I wired. Any ideas? If it helps, I've connected the following:
red +12V constant to constant +12V in ignition switch harness
yellow +12V ignition, via the pre-wired starter kill relay, to +12V when ignition "on" in the ignition switch harness
black ground piggybacking a factory ground location
blue (-) instant trigger to hood pin (added) and factory trunk light switch
green (-) door trigger, wired with domelight supervision relay, and tapped into the cluster indicator for door open
red siren lead to brown wire from brain
black siren lead grounded with the brain ground at the factory ground location
white parking light flash to multi-function switch (-) with brain jumper moved to (-)
valet switch plugged into brain
LED plugged into brain
dipole antenna plugged into brain
shock sensor plugged into brain with green wire loop at the sensor end
At this point, the door lock harness is not connected. I installed a SPAL central locking kit, that uses their so-called M5 module to control the actuators. Still trying to figure out how to connect the door lock harness to the M5 because I understand it's basically a relay pack. I know if I back-probe the M5 harness connector with the purple wires with a ground, the actuators lock. Then if I do the same but to the terminal with the brown wires they unlock. Seems like all I would have to do is connect the green of the door lock harness to the purple at the M5 and then the blue to the brown and I should be good. Right? Do I need diodes? Which way would they face?
I would SINCERELY APPRECIATE any insight to solve this!
THANKS!!!!