confusing error message and a couple other probably beginner blueprint questions

Hi, i am working on a game in which you bounce a lazer between mirrors image: but whenever the lazer is not hitting the mirrors i get this error over and over: . im not sure what this means or how to fix it, also is it possible to condense a massive set of blueprint nodes into one so i dont have to copy it every time i want to hard code in another lazer bounce i.e. : [URL=“”]]( the copied section to allow the lazer to bounce a second time is selected in orange. it would be nice so it wasnt such a huge clump to copy and instead a couple nodes.\

Thanks in advance

Just FYI, only people with a Google account are going to be able to view your images.

Upload them using the forum’s built in attachment system instead.