supports for an existing character and adding a new one
Yeah, that's a little odd. When you select your GameData.bin, that prompter at the top should change from "Please Select GameData.bin" to "GameData.bin Loaded." It looks like something got messed up during that process - it's definitely a bug. I'm actually having trouble reproducing it though. Do you remember what you did before you encountered the bug? Everything shows up correctly for me when simply opening a GameData.bin and clicking on a character.
Alternatively, it could be an issue with your Supports.xml, as I've already found some odd behaviors with that file. You could try replacing your Supports.xml with the one that came with the download and see if that fixes the issue.