Don't blow up if there is no prescribed motion (problem in Debug builds only).
Don't blow up if there is no prescribed motion (problem in Debug builds only).

scamille/simbody,Gjacquenot/simbody,simbody/simbody,chrisdembia/simbody,robojukie/simbody,Gjacquenot/simbody,chrisdembia/simbody,scamille/simbody,simbody/simbody,elkingtonmcb/simbody,chrisdembia/simbody,scamille/simbody,robojukie/simbody,Gjacquenot/simbody,elen4/simbody,elkingtonmcb/simbody,robojukie/simbody,elkingtonmcb/simbody,elen4/simbody