1: Function PlanWizardDatabase.GetNextNumber() as int32
2: Function PlanWizardDatabase.AddObject( int32, int32, CatalogueFind ) as boolean
3: Sub PlanWizardThread.Event_Run()

User description of above error trace:

I tried out the plan wizard to find as many easy Planetary Nebulae as possible (max objects 500)

This is probably a side effect of using the plan creation wizard while the background thread that collects info from the catalogues is busy.

Fixed. If you attempt to use the PCW while the background thread is busy, you'll be asked to come back later.