When I look at a building and use the /own all command it only changes the owner of the one building block or deployable I am looking at and not the connected entities. Not sure why?

Same problem here.
The function does not detect nearby entites.
Maybe you want to look at the copyPaste-plugin. He uses another way to detect nearby entities and that works fine :)

*cough*

Same Problem here

Seems to have been broken since 3.1.8 since the parameter `all` (and others) are not evaluated any more. You can try adding the following right after line 381, but I expect it to break in other ways since it has been inactive for so long.

type = args[0];