So I got the progress bars working again, shame I broke a few other things.
Cocoa's auto-release of memory makes using threads a little more
interesting than I like, as objects frequently get released in the middle of a
child thread run.

Bindings do not play nicely with threads either, I have to force the main window to update at the end of the threads to bring the flame list up to date
after adding a new flame.

The good news is that everything bar the breeder window now renders multithreaded
with updating progress numbers (I took the bars out, and need to put them back).
The breeder window is next, it should be another

After that, I've got a few bugs raised on Sourceforge to fix, then it's
release time.