I think I know what the problem is now. One of the add-ons were downloaded in the wrong spot, because I just went on a server called "freebuild" and I was downloading so many add-ons that I already have. I still remember one of the locations of the files. The destination was Add-Ons/Add-Ons/(filename)/(filename). Right now, I'm looking through my Add-Ons folder for any suspicious files in the wrong place. There were some misplaced items I just found, like the Crossbow file. It was this: C:/Program Files/Blockland/Add-Ons/Crossbow/Blockland/Add-ons. There was a strange incident when I took the screenshot. The paint, block, chat, and crosshair all went away when I took it. The time I took the screenshot was the same time the cursor appeared while I was on a server, which was the first time it happened.