[Gregstrom]

Ah. In the course of surveying neighbours for 46, I think I worked out the problem.

99 was stated to be be a start point, but wasn't set as one in the initial mod. 99 is adjacent to 46, which meant when it was set as a start point, it could maybe exclude 46 from selection.

Luckily, 46 has too many neighbours anyway and so I can cut it off from 99. I'll see if that sorts it out.