I have a small DF-20 application that started out in 19.0, then 19.1 and now 20.0. After moving it to 20 shutting it down results in a chain of the following errors, any idea why?

Click image for larger version. 

Name:	prepareparms.jpg 
Views:	65 
Size:	6.6 KB 
ID:	14632
Click image for larger version. 

Name:	defineparam.jpg 
Views:	46 
Size:	6.3 KB 
ID:	14634
Click image for larger version. 

Name:	invokecommethod.jpg 
Views:	40 
Size:	6.8 KB 
ID:	14633
Click image for larger version. 

Name:	releaseobject.jpg 
Views:	43 
Size:	6.3 KB 
ID:	14631