And then you can't even go back to copy / paste what you were typing, lol. Makes you wanna slit your wrists!!! K maybe not that much, but it's pretty annoying.
What does your plug look like each time it goes? Crushed, burnt??? This happened before and after the MSP ECU went in right?? I'm wondering if it would be worth getting the wires in the harness checked. Could possibly be a short going towards the coil or the injector. It could be a fuel problem to that cylinder. Try swapping the injectors from one cylinder to that one and see what happens. You've already done all the first steps really that could result in a problem like this, so start trying the unlikely things.
I was going to say peek inside and see if you can check the condition of the top of the piston. Hopefully there's no contact there. Someone's already mentioned that in the other thread though. Aside from the timing that's been mentioned, the only other thing I could think of is the fuel delivery. Any misfire CELs besides when the plug gets destroyed??