Yes, you weren't too far off the money with the resistor change.
I've had mains that were still being tweaked and modified after 2 years so 1 week is cool and shows the planning and number crunching paid off. The bulk of the xo came from the original Scan Speak speaker which saved a lot of time as that took ages and almost went to a parallel xo (sorry about that word) as there were problems getting it right in series, but the AR xo saved the day.
