JaVaWa RTWtool is a program that allows various conversions of routes, tracks, and waypoints. There are options to 'unflag' routes, convert routes to tracks and vice versa, convert a collection of waypoints to a track or direct route.
Routes and tracks can be filtered to limit the number of points per route/track, and they can be split if they exceed a specified length. Tracks can be joined together.
Tracks and waypoints can be enriched with elevation data, and tracklogs can be cleaned up.
It is a great tool for tracks conversion.