It's not legal in wxWidgets to set an object derived from wxWindowBase to be its own drop-target, for the wxWindowBase destructor will unconditionally destroy its drop-target (ie. itself). See the implementation of the wxWindowBase destructor:
Because of this, the current implementation of MeteoriteDialog will always crash with a SIGSEGV upon exit. The attached patch solves this by moving the OnDropFiles() method into a separate object.