Installing Cradle for my Wikibase instance

Question

I set up my wikibase instance with my mediawiki instance on my own server. I want users to be able to create wikibase items for each wiki entry manually by entering data in a custom data entry form. (I want to display this data in an infobox on each wiki entry later.) The wikibase documentation lists Cradle as the tool to do this. I think I understand how to use cradle once it is installed, but I am lost trying to install it in the first place.

The setup instructions are scant and I have several questions:

1. Which directory should I place the files into to install: into my server root directory, the wiki directory, or the wikibase directory?
2. Do I somehow create my own cradle url on my server to use the forms I create via the cradle page on my wiki (as outlined here) or do I have to use this Cradle instance on toolforge, which seems custom to Wikidata? In short, how do I get to use the forms I create?
3. How do I then update the config.js? I think I have my source page, wikibase URL, and wikibase api URL, and I think I have figured out OAuth with the correct URL. The cradle specific URLs I am not sure of (but they are probably related to question 2.). Can I update this on server after the install or do I have to reinstall?

I am sorry if these are basic questions with obvious answers, but my skills here are limited. I would be very happy for any pointers! Thank you!

UPDATE: I figured out the directory problem, I think. I simply put it in the root folder of my website and then entered the file path to the public_html folder as the url. I got the "Loading" message which the toolforge version also has, so I think I am on the right track. So I entered that URL as the cradle URL and API in the config.js. I reinstalled, but the screen still gets stuck on the "Loading" screen. At least now I know the answer to question 2: I create my own Cradle instance. So now I am not sure what is wrong. Is it the config.js settings or the OAuth? My config.js settings are:

'use strict';

let config = {
"source_page":"MY_PROJECT:Cradle",
"wikibase_url":"MY_WIKI_URL",
"wikibase_api":"MY_WIKI_URL/api.php",
"oauth_url":"MY_WIKI_URL/index.php?title=Spezial:OAuth",
"cradle_url":"MY_WIKI_URL/cradle-master/public_html/",
"cradle_api":"MY_WIKI_URL/cradle-master/public_html/api.php"
} ;

I registered and approved Cradle with OAuth, entered the keys and the correct name in the oauth.ini in the cradle root folder. I tried the OAuth 2.0 and 1.0a connection. Is there something in those settings to look out for?