Hi,
I'm not the ideal person to help you, and possibly what I say can not result in anything. But you can try, do not be afraid of the code, if you lose it or have questions, you quickly restores backed up, right?
in map.php, replace the variable "$item" for perhaps "$user".
In index.php, replace the "$aItem" variable with "$user".
Still in index.php, replace the variable "$itemId" for "$userId".
the variable "$catId" you should not need it in the function, because it is the id of the category.
You can try, but as I said earlier, I have no certainty of anything and did not even try to do this test.
Sorry if i'm wrong, i never tryed this before
Use \oc-includes\osclass\helpers for you see some variables that may exist... i dont know.
Regards