Yes.
If you did an upgrade from MC20 to 21, then any custom Theatre View Theme images you had would not have been moved from the MC20 directory structure to the MC21 structure.
Theme files are located in the following folder for MC21, and a similar one for MC20, where "MyTheme" is a folder you have created that holds your custom theme. I copied the Default Theme and then replaced the default images with my own in that directory.
C:\Program Files (x86)\J River\Media Center 21\Skins\Theater View\Themes\MyTheme
Once you have the folder in the correct location, with your images in place, go to "Tools/Options/Theatre View/Appearance/Theme" and select your new custom theme, which has the same name as the directory you created. Note that there are a whole lot of other settings in there as well, which you should look over.
Easy. But you have to remember to move this stuff for major upgrades. Well, I don't think they are supposed to get moved or copied automatically. Certainly my custom theme wasn't automatically copied from MC20 to MC21.
It is a bit strange placing images under the "Program Files (x86)" directory, rather than a user directory such as "C:\Users\[UserID]\AppData\Roaming\J River\Media Center 21", or even pointing the Theme to a photo collection stored somewhere else. But I am not aware of any way to place Themes under a user directory, or point to another image location. If someone is aware of somewhere else custom Themes should be placed, please speak up.
