What is "everything" you swapped over?
If you swapped the ECM, but are using the same original keys, they would not be programmed into the new ECM yet, or whichever separate security module if it is separate from ECM. If there is a separate security module, and it wasn't swapped, then some of what i wrote below may be incorrect and I don't know the interoperability between the separate modules and ECMs.
If you have NO keys already programmed into the new ECM, and don't have the keys that were programmed into it, you can use a windows host, forscan ("pro"? version) and an OBD2 dongle to program keys, or have a dealer or locksmith do it for your original keys. If you do have the keys that were for the donor vehicle that the new ECM came out of, in theory you could use those to program in your original keys for the ranger. You'd wrap foil around your original Ranger keyhead to block the chip in it, and hold the key head for the new ECM very close to the ignition ring, going into program mode you would do this for the two keys original to the new ECM, then when you get the chance to program in more keys, take the foil off your ranger original keys and put the new ECM keys aside. Heh, I hope that makes sense.
What vehicle did the new ECM come out of? Explorers, were injector disable from '98 till about '01, then starter disable after that, and IIRC some vehicles with European security setups, also had a fuel pump disconnect module at (near) the tank.
PATs does blink once every second or two in standby, key out of ignition. It comes on steady with key in and blinks fast if there is no progammed-in key detected.
If your fuel injectors are not firing you should be able to measure this with a multimeter.