[ScorpioJonesy]

Is there anything special that needs to be done if using a central MYSQL server?

No.

I don't know why it has "C:\Upload\xbmc_videodb_2015-11-22" in the path?

Because that's the artwork path you have in your MySQL video library - presumably that's where you scraped the artwork from, or exported/imported it to/from.

Try running .\texturecache.py jd movies "Zero Dark Thirty" and you'll see the artwork paths being used by the movie. If the paths are incorrect you'll need to fix them - have a look at the mklocal.py link at the foot of the first post as it can help get your artwork back in order. 

 Thanks for the info, I did some checking using the script and it seems something had gone wrong with the library so I did a full reset and rescan. All looking good again now.