If any other users have any experience with this I would really like to here from you as to how you enter a combination Spiral or single Spiral Based on the following known factors: 1- PS, 2- Known Forward Tanget, 3- PI,4-Tangent Length & Direction both in and out., 5-PT I can figure Spiral Deflection long hand based on the Oregon State Highway Div. Standard Spiral manual. The terminology that I am used to using are Curve Radius, Length of Spiral and the “a” value simple as that. Help menu sent me down a rabbit hole! I did eventually get it figured out after 6 hours!
If anyone wants a solution to this I may have one, Now that I have it in 3 seperate pieces and would like to make a R/W offset to determine found monument stations but that might be another whole day.