Changes for v1.91 are:
— Adds support for the new Border Spline primitive (Wall Worm) and NGon by Edge (Swordslayer)
— Adds an Interpolation Multiplier option for splines
— Adds a Test Splines option to collect data about splines that might cause issues
— Adds a button to select splines that have overlapping vertices and highlight those locations
— Adds Force Steps and Force Steps Amount options to override the interpolation steps of splines

CorVex is available for Max 2010 to 2018 and costs $10.