I read Peter Smit's bible on g code to understand what G28 was about. I suspect the reason I edited my post was to ensure it actually did what was required ie retract fully to machine Z home position. Don't recall the specifics but I may have struggled to understand what Newker were actually doing with it.

I also ended up rewriting the tool length macros because they didn't work correctly, something to do with my machine being a knee mill and they probably targetted a bed mill..

You can edit the post processor easily enough to spit out the correct g code for end of program, tool change etc. I also put in an option to decide whether to move the table to an accessible position after finishing the machining. That comes up as an option in the Fusion dialogue box when you post process the job.