How to properly shut down everything? (SWC v1_0_279)

[2DGuy]

Error #1009: Cannot access a property or method of a null object reference. at com.genome2d::Genome2D/g2d_frameHandler()

I can't find out what to call,dispose, etc, etc, to remove this error when I shut down the app. So, what exactly do I need to be calling to shut down Genome2d before I exit the app? Thank you.