This patch comes with a number of updates and bug fixes for the Track Editor:
• Context menu added. You can access this through LCtrl + Right Mouse Click
• Added Box Select to Track Editor. L Ctrl + Left Click and drag to select entities in bulk.
• Added Track Node refresh button. This will re-connect any disconnected track nodes from editing.
• Fixes a bug where old physics meshes could be duplicated when track nodes are modified, causing racers to randomly fly off.
• Fixes null error when some nodes are deleted.
Track Editor Patch - v 0.8.4.183
Source: Steam Community (opens in a new tab)