Join the "I can get my 1.4 AEX to work properly" club. I'm a member already.
Fuel sounds like some sort of overfueling or leak. I'm reading though the other posts.
I see tank sender has already been suggested. I'd also check the joints on the feed and return pipes as being old and having been pulled of and put on a few times the ends may be damaged.
You can't alter the timing by moving the distributor, the ECU corrects for it sort of, IIRC. It has to be done with VAGCOM and a strobe light.
Also consider the coolant pump, they seem to me to be very fussy on this engine (or maybe most Golfs I don't know) but the slightest damage or fault and it shows up in the cooling system somewhere. I've swapped one where there was a small segment missing out of the impeller but several people had said that there was a problem with the pump.
Not having clips on the pipes to and from the carbon filter in the front corner of the engine bay may be a cause of you smelling fuel.
Agree with another poster that the ECU being duff is very unlikely.

If you can afford the fuel and can get over to me I have a compression tester we can use.