Sounds like you've found the fault with the transformer and it sounds like it's a failure in the primary windings? That's if I'm reading what your saying correctly (I don't have and so have not looked at the schematic, but am assuming F6 is the 240V inlet fuse) and if this is the case another test you could do to confirm is to measure separately the resistance of each of the two primary windings. There should be a large difference between the two to account for this failure if the suggestion is that one of the windings has shorted?
If it's stuffed then who cares, but maybe this is interesting?
