Looks good. Personally, I'd put the XLC in the gid to the BACK of the grid, to avoid a pileup at the start of the race, not to mention forcing the last 4 cars to be so far behind the leaders. ;-)
I don't think you can do it with the APB yet, but with the PB-Pro C7030, it can disable lane changing for the first X seconds of a race. That works nicely on my track. Hopefully such a feature will be added to various RMS apps for the APB. It'd be nice to see that added to the standalone code, too, but I won't hold my breath for that.