* Does not properly load woofer diameter from a saved file.
* Does not properly display INVERT/NORMAL status from a loaded file (gets fixed when you click invert twice).
* Window does not properly fit in the frame, I have to scroll up to the top tabs all the time.
Good job! I'm sure with time this will be perfect!

Also, a comment:
I expected the Transfer Function pane under System Graphs to have a relative index on the vertical, centered on 0db. Does that make more sense to anyone else too?