So, I woke up this AM thinking about this. The two plans are identical, except for a small straight section on the return loops. The variance between the 2 programs comes down to AnyRail calling for 3 pieces (one 4.5" and two 1.37" totaling 7.26") and SCARM calling for 4 pieces (four 1.75" totaling 7").
SCARM measures the actual gap at (approximately???) 7.1". I'm not sure how to measure a gap in AnyRail.
When building, I'm going to try and remember to experiment with both and see which one is more "right"... Maybe they're both right???