This is actually quiet simple if you follow these very easy directions.
1. First find the Add-On you want to get click the link to download taking you to were that person is hosting the file (Mediafire, File Front etc.)
2. Then click on the Download button ONCE or you will have a copy, then go to your Desktop go to the top right corner were Spotlight is and start searching Downloads.
3. Open that file and you should see the Add-On you downloaded then go back to Spotlight and search Add-Ons or you could go to your Blockland Folder and open it.
4. Then drag that file into your Add-Ons Folder.
5. After that open Blockland then click Start A Game. Do not start a game first go to the bottom of the Start A Game window and click Add-Ons.
6. Find the file you downloaded and make sure the box to the left of it is checked off and your done. Have fun
