Hotfix 1.17.18

UPDATE: Viafier Retica initial traffic streamlined to prevent conflicts

FIX: Map was not loadable if it contained an arrival sensor referring a deleted platform
FIX: Regional train in shunting mode leaving the map caused broken save
FIX: Train on platform did not move with 'Go to platform' shunting command to other platform currently executed
FIX: Tunnel length value was not accepted in Editor