have expert config dialog survive exceptions

Change-Id: I78a8cd4fff8fb134679d2223a379b6eb799d6f05
use define rather than raw numbers

Change-Id: I62802256780abe92f89a8cde066b26353fc3362a
Resolves: fdo#73806 reduce the size-request of the expert config dialog

the optimal size was set to be 1024x800, reduce this down to
effectively the same size as the options dialog itself.

This dialog just isn't ever going to be right given the huge
length of the strings and the number of strings. We need
something more like a file picker dialog view here

Change-Id: I019e951601c3df769a609b8b439b535b6d5e254f