Insure that after the Droplet is created in the Resource Manager to import the SSH key (add to SSH agent by right clicking it). Then, an important step that should be documented, is to go to the Digital Ocean Dashboard and connect to the Droplet using their SSH tool. This in-turn will allow the new SSH key to be used for future connections, ie from within Wappler. If you don't do this you may find yourself not being able to Deploy or Restart the Droplet etc...