Sandbox- Repeated crash trying to go from Earth to Mars

I've set up a sandbox using Earth and Mars, with the 2018 transfer opportunity. Problem seems to be after leaving Earth orbit, using Sol as the reference body, the maneuver orbit projection computes out more than 7 years of future trajectory and brings the program to its knees. after a couple of attempted burns it crashes with an access violation error. Any way to control how far in the future it computes? Or make it not crash? No crash log btw.