Errors on my errors?!

[Your Computer]

I think it would be easier for the both of us in helping you understand the error itself. When it says "no matching signatures to <function here>" it means it couldn't find that exact function, neither in your script nor from the game itself. This is often due to a misspelling of the function name or not filling in all the required parameters to the targeted function. Parameters are those you pass into the function (what goes inside the parentheses).

I should also note, it is often better if you read the error message from bottom to top. In this case, what is wrong with SetEntityActive() in your script? Is there anything missing from it?