If you get cryptic or useless answers it's often because you have not provided enough info, so that other people have to guess what you want. Sometimes they miss with the answers, other times the people with the questions misunderstands the answers. Sometimes the users does not signal what kind of knowledge they have of the product, so they answer you in a cryptic or to simplified way. It first seems like you have full control of theater view customization, because you're in the folders and messing with the files and you seem to have been doing so for the last 3 versions. But in reality you do not know much of how the underlaying systems work. At least it seems like this to me.
The JRiver forums are one of the best help and support forums in the world I think. I'm active in quite a few, and I've seen my share of hopeless support. Here you have very knowledgeable users, that is often very quick at helping out. There are several super active and smart users on this forum that are willing to spend literally hours of their time to help users with problems. You also have the developers who actively use the forums and help out, and they actually listen to the user feedback. So, I do think it's unfair to judge them based on such a bad forum post.
You've basically just said that you want to change backgrounds in theater view. You say you're messing with the theme folder and that you're not interested in online backgrounds. It's not strange that Matt answers the way he does. I think many of the experienced users would jump to the same conclusion as well.
Static Backgrounds in theater view is based on the View's name. It has to match, and you can only have one static background for each view. Like movies view with a movies.jpg image, main menu with a root.jpg (?) image, Audio view with a Audio.jpg image and so on. And as Matt said, those images will only change when you actually change a view. If you had provided with exact paths and file names, as well as where you wanted to show those backgrounds, I'm pretty sure you would have gotten the correct answer in the first replay.
