I've just installed on mediawiki. Everything installed properly but there are some differences between what I'm seeing and what I'm reading in the help.
Special:Attributes lists nothing
When creating an attribute, the listbox (hope I have the right term here) points to a page that is not of the state Attribute:...form. For example, I've used [[Written on:=2006-07-24|July 24, 2006]] and the listbox example links me to [[Written on]] and not [[Attribute:Written on]]. Then, when I set a date type as per instructions, it says the date type is invalid. Same for integer on another example.
What does seem to work...
Special:Types lists the same as the ontoworld site.
Would love to know what I'm missing.