Thanks for your report. The 'RoutePlanner' path finder is still under development and not really stable, yet, so there are known issues with it. Silnarm, who develops it, may be interested in your log files, though. Be sure to set DebugWorld=true in glestuser.ini when testing path finders.
When you are reporting issues in a development version (i.e. when you checked out from subversion and compiled yourself) please be sure to include the subversion revision your report refers to.