I forgot to add this to the initial email
See pages 51-63 (printed pages) from the manual of SCORE to get an idea of what controls the slurs/ties might need to have to approximate the intended functionality.
The important things are:
• maintain as much as possible of the default Lilypond functionality
• the flatness/curviness adjustments
• the ability to make slurs asymmetric. This important for slurs with an angle pg. 59),
• ability to have an incomplete flattened slur/tie for when system/page breaks happen or other rare edge cases
• keeping functionality of the dashed variant
• should work with L.V. ties as well
• ability to define different curvature for the after-line-breaking portion of the slur/tie