[huttdes]

Also I tried to add a fictitious 'studio' in my nfo... nothing showed up. Is there a way to make this work (preferably with my own custom logo) or will Kodi only recognize genuine studios?

Studio icons are a downloadable Resource addon, which is different to simple user artwork.

The icon pack is here... https://github.com/XBMC-Addons/resource....s.coloured You would need to unpack your local xbt file and add in your new studio icon.

As for the actors images, in which nfo file are you placing them? The tvshow.nfo file or the episode nfo file? And where are you looking to notice they are missing- tv show info or episode info?

There is no <profile/> tag. You should have <order></order> instead (but it is optional). This controls what order the images are displayed when you view the actor listing in the Information Page.

All filenames for actors must contain the underscore in place of any spaces. So John Smith actor would have the image saved as John_Smith.jpg 

I have every actor option listed in the show nfo. And I have whichever ones appear in each episode in the episode nfo.
That </profile/> tag had to have been added when Tiny Media Manager was doing this for me and I left it in.
So to confirm... the filenames will have the underscore but in the nfo I will have an actual space?

So here is where some of my confusion came from... actually still confused.
Over the many years of using this I have primarily used 2 media managers for Kodi. MediaElch and Media Companion.
So I'm looking through all my shows...They all have actor images in show nfo. But for the episode nfos so do and some don't. But in the wiki link you posted what I got from it was they are in both.
I have shows ... say The Simpsons for example that definitely show different actors for different episodes... so I assumed this is how that worked but listing them in each episode nfo.
Also all shows have a .actor folder in the shows root folder... but many or most also have a .actors folder in each episode folder... this is the reason I originally thought I could do what I wanted using the same actor names but different pictures. I thought it checked the season actor folder for the art.
So since I haven't consistently used the same media manager I don't know which did what.
Should I assume all the actor folders in each season are actually useless and I should just have a single actor folder in my root folder?

You said you do your stuff manually but I just assume you meant for project like I'm working on for home movies.
What do you do with actual TV shows? Or do you let Kodi scrape and export the files to be stored locally if you want?