Mo,
As I understand it they're not added automatically, but reviewed 'as and when', with a possible backlog. Once added to DT the original post of the lyrics is identified by the addition of a 'little bird': '^^@.
When linking (creating a Blicky) from Mudcat to a page within Mudcat you don't need to include the whole of the address shown on your browser, ans this sends the request into the world wide web, only to redirect here. Just use the section after the last '/'. So for a link to this page from somewhere else on the www you would need to include:
https://mudcat.org/thread.cfm?threadid=168386&messages=1 (or, as number of messages is additional info, just: https://mudcat.org/thread.cfm?threadid=168386
For a link from within Mudcat, either in a thread, or in a PM you only need to include:
thread.cfm?threadid=168386

Hope thie helps