Thank you! I’ve seen scripts with .bat files to install/update web sources but not sure how to really do it properly so apologies if it’s not been clear how to deal with installation. Here’s a link for future reference Web Sources Archive - Howto - Mp3tag Community
@RobertM ’s been great and I’m chuffed he’s looked into the matter 
Unfortunately Mp3Tag’s current method is strictly TRACK generates an array of results and is always to the left, then TITLE then any other tags in-between. The intention seems focused on music files rather than video which for a program based on MP3’s is completely valid.
The script does return results by your given episode order so it should be TVEPISODE 3, 7 and 15 even though TRACK makes it look otherwise. I’d love to have a way of determining an ordering of tags for the Tracks section and will pitch that to the developer.
I did look into TVDB as an alternative but apparently it’s falling apart in terms of developer support. Fair enough using it for pre-existing content but not sure of it’s longevity. Hopefully I’m wrong but avoiding it for now 
Please let me know what tweaks helped you for your language, I use English but want to try supporting multiple languages I’ll aim to provide update within the next week as I noticed some problems with ITUNEXTC, INVOLVEDPEOPLE and SORT tags