I don’t know what might be going on with the program appearing to hang when you extend a note.
You should be able to select pedal lines in much the same way in Dorico for iPad as you can on the desktop – I’m not sure in what way you might be having problems selecting them?
As for finding diagnostic reports, crash logs at least can be found on your device and then shared to another device, and if you wish you can certainly send them to us by attaching them here. I describe the location here.