Hi there!
I see two problems on your screenshot, the first one is a silent error on EliMZ_WindowSkin, but you need to fix it in order for the plugin to work. This probably is related to a plugin parameter you didn't set up. So go into the plugin parameters of this plugin and make surre you have all properly filled.
The second error is the crash that happens in battle. I believe I fixed this issue yesterday. You need to download the latest version of my Eli Book plugin, which is the core plugin for all my plugins.