Your image is not loading for me, so I can't really help too much right now, but when you get the error, could you also press F12 to open the developer console, click on the "Console" tab on the top of the window that pops up, and take a screenshot of the text in there? That will give us more information on how the program got to the place where it encountered that error.
Also, just to be sure, are you using the most up to date version of the plugin? Is that the only plugin you have? Yanfly plugins typically have at least one dependency, unless it is just a core script. Please let us know about all the plugins you're using.
