Apologies - spent a bit more time playing with this and 'kinda' figured it out, in case anyone else finds themselves in need (although any better ways of getting the MIME type would probably not be a bad idea):
Didn't realise but one of the File functions (LoadBinaryFile) in a calc stage has the ability to convert a file into binary data, so that was the first problem solved. As for the MIME type, I made up a collection of the common file extensions we may end up emailing (came up with about 18 at the moment) and then looped through this collection, comparing it against the extension of the file I was trying to attach. Works a charm now!
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John Hammond
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