You Must Use Blender or some sort Of Application To Model,Script,And Create the Add on. If this isn't they way it is done Please Ask someone Who knows How.
You can get Addons from either: -Blockland Fourm's Add-On Page -Return To Blockland
Yes, to add addons to the addon list in Blockland, you typically need to extract files from the downloaded addon ZIP or RAR archive. Once extracted, you should place the files in the appropriate "Add-Ons" folder within the Blockland directory. After that, the addons should appear in the game's addon list when you start Blockland. Make sure to restart the game if the addons don't show up immediately.
you go to the blockland forums like here: http://forum.blockland.us/index.php?
return to blockland is an free version of blockland but it lags by bunch of bricks and there you can see more about torque engine and normal blockland has more like addons and more maps and official website but return to blockland has only bunch of Lego weapons and items and Lego bricks! here isn't physics and there is multiplayer! you can save things and load it again.
find one of the blockland sites
In the demo you can't create or join servers, load more than 5 addons, or place more than 150 bricks.
No.
Make sure your driver is up to date. Try to ask help from the people of the Blockland Forums.
Depends on what addon you want to make...
Byuilding and eventing one.
Blockland generate key online: infiles.org/blockland/
You have to go to Return To Blockland to download stuff for Blockland.