heater woes Options

[cause]

Finally assembled all of the missing bits to put heat in my car—however I am now running into electrical issues it seems.

what I think are two separate issues I'm experiencing:

1. When testing to see if the fan works at all, I had it disconnected from the main wiring harness and used a jumper wire to connect it directly to the battery—which it does come on, but doesn't need to be grounded with the second wire, is that normal?
2. (Without the fan plugged into the harness still) Only when I have the relay in the circuit board and when heater lever is engaged it sparks and the wire gets super hot/melty. I understand that its just a ground wire, so where could the voltage be coming from and shorting out?

If any folks are decently local to NY/NJ area I'd really appreciate extra eyes on figuring this out—im so close yet so far. :/

[cause]

Well, idk what I did—but I took everything apart and put it back together again (for the 15th time) and now everything works...