[egpetridis]

Ok, I did not realise you were trying to create a Combination NFO. Your post reads like you are trying to create a Parsing NFO.

One would have thought that the Universal scraper would have no problem picking the correct movie, as I've already described its IMDB URL.

I will have to look into it further. Although, I do question what you are hoping to achieve with your example nfo.  

 There certainly is scope for such nfo files; Take the following nfo for example:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<movie>
    <genre>Adult</genre>
    <genre>Porn</genre>
    <tag>porn str8</tag> 
    <id>tt6127900</id>
</movie>
http://www.imdb.com/title/tt6127900/

I'm trying to set my own tag and genre attributes, regardless of those in IMDB or TMDB. What I was hoping to achieve as you kindly put it, was to add my tags to those of TMDB, it seems though that when tags are described locally they're not appended to those of TMDB but replace them. Odd thing is that there is no mention of such behaviour in the nfo attribute description. Certain attributes can be optionally set to replace those in IMDB (by inclusion of the "clear" attribute), therefore the rest are implied to be used to add rather than replace infoprmation, especially on repeatable attributes.