The duplicator should be made default

[Katadeus]

Are you sure you're using the blockland folder under My Documents?

[Ad Bot]

[Igloos]

Are you sure you're using the blockland folder under My Documents?

Yes 1000000000%.

[Zeblote]

Ok you are obviously not finding the right add-ons folder.

Make a new folder somewhere on your computer, name it blockland
Extract this zip file into that folder: http://blockland.us/files/BlocklandPortable.zip
Run the .bat file
That now created a new blockland installation, and the (working) add-ons folder is right there in the folder you created.