The Linker is a great utility! I used Star-Linker on a project of mine which mostly works; it was for a BBS sysop friend of mine who was writing his own Commodore BBS in Java -- his Java PETSCII file read routine could only understand comma-separated values in a file. So to clear the screen, it would be 147,14 to change to lowercase,etc. The end of file was denoted by 0, similar to requirements for DotBASIC's .BL command.
I came up with a mostly-working program using Toolbox 105, very GUI-fied, but there are a few bugs in it yet. I might re-visit it and see whether Metal Mage still has a use for it.
The SID driver is in fact Craig Chamberlain's Enhanced SID Player, so anything that has ever been on LOADSTAR, or .MUS files, should work. The SID's IRQ is wedged beneath the mouse/DB IRQ, so it work with the mouse and any other event driver.