@wgstarks & @bmartino1,
Thanks for your detailed answers!
So, if I understand correctly: First create the mongo-init.js file in a location of my choosing and fil it whit the correct content as stated in the github page, After this deploy the MongoDB container with the correct path configured & manually adding the file name to the host path parameter?
I do not need to set certain access rights? The defaults from Unraid are sufficient?
I will try a new deploy on Friday when I have some time, will report back with my findings.