Check for rogue waypoints.
If you group waypoints in WC and then go and delete them, remnants of that way point remain in the map. In addition, overlapping waypoints can be overlooked if you group them and forget they are grouped when selecting to troubleshoot.
Please post the waypoint x/y/z coordinates in the Swat error. You can located the problem waypoint with these properties using WC.
Before attempting any of these troubleshooting tips, back up your map's rmf
Try this first - check for rogue waypoints (entity remnants), set your upper tool box to selection by handle "x" in the center of the objects drag a selection over the center of the map maybe 4 by 4 unit selection box, Wc will notify you if you have an object or entity selected by showing you its x/y properties in the selection properties section at the bottom of the application window, The properties of the rogue objects or entities will read -9999999999.999999 , while you have them selected ungroup then reselect and delete.
I will try to get my _waypoint_HELP.txt pages uploaded so you can check for other issues.