Damon,
Not sure whether it's your choice of Coordinate System or what, but here's what I did. In Ambient Settings I selected "Decimal" for Lats and Longs. I assigned AMG-54-Grid as the Coordinate System. Using the PLine Command and the Transparent Command 'LL I drew a PLine here:
From:
Julia Creek, QLD
20.6562° S, 141.7442° E
To:
Kynuna, QLD
21.5783° S, 141.9222° E
Dave
Dave Stoll
Las Vegas, Nevada
64GB DDR4 2400MHz ECC SoDIMM / 1TB SSD
NVIDIA Quadro P5000 16GB
Windows 10 Pro 64 / Civil 3D 2024