Well I finally got the job done with a combination of filling the gaps with Super Glue, and tapering the very ends of the fret down to meet where the nibs started - they were actually sitting just a fraction lower then the frets themselves, meaning there was not only a gap, but also a step down to them too. End result, a much easier experience when playing. I'm still not convinced it's a perfect solution, as I think only a refret would achieve that, but it's far more playable for me now. I'll give it a bit of time and see how we go. Thanks to everyone who chipped in with their suggestions, especially GuitarDoc.
