Part MultiLevel BOM

I added a new field in my "Part" item type that's is called "master file" which is an item type that comes from the FILE item type. I changed the PartLevel BOM code so it displays in the BOM Structure. My two issues are:

1. How can I display the keyed name for that file instead of the ID. I changed the GetMultiBom method from:

infoOfItem.file_master = itm.getProperty("related_file_master", "");
to
infoOfItem.file_master = itm.getPropertyAttribute("related_file_master","keyed_name","");

but that didn't work.

2. How can I make that field act like a item type field so it's clickable to display that item? It's only displaying the ID number and I'm not able to click the ID to display that file. - see attachment.