Beam me up, Schottky!

So, I think I finally figured out - or at least the remedy for - why the extra cables were needed. 

It was pretty much as I expected and that voltage somehow got reversed in the circuit, and me either knowing too little about electronics or expecting too much from the power supplies. Rookie mistake in assuming the power supply would overpower the other components, but it seems that it doesn't. 

Long story short, it would seem that the capacitors I have on the PCB is enough to offset the "power balance" in the board, and by connecting the power lines to the ChipKit's lines I basically hijacked the voltage rectifiers to "heal" the PCB. 

By replacing the fuse with a diode (temporarily) all of my problems goes away: 

1) It ain't safe and it's not pretty, but proof is proof. 
Notice the disconnected +3V3 and +5V cables. 

Oh, fun fact:
Turns out that the +3V3 cable wasn't really needed.
I had damaged the trace on the board while removing the capacitor
in my first feeble attempt to solve the power problem a year ago or so. 

I used diodes to force current this or that way on the board, but forgot/ignored the main lines since I assumed they would be alright coming directly from the PSU. 

So now I'm basically trying to find a way to incorporate diodes (Schottky's) in series with each power line. The voltage drop isn't that bad (-0.48V) but still a lot more than I had hoped to achieve. I want to avoid having several boards and something like the below should probably work, but I could also use a P-channel MOSFET as a very low resistance diode. 

But I'm going to try to use a setup similar to the one at the top in the above image, where the diode would be standing up and connect to a vertical mounted fuse cylinder instead. It should work, and it seems there's enough space. Would be nice to get rid of this pesky power problem once and for all. 

But we'll see.