Bob:
No other suggestions. I checked Roots Ireland and found the baptism record that you have for Margaret in 1829 but I was unable to locate a record for Stephen or Jane. The availability for some of the C of I parishes is much later than you need e.g. Conwal and Convoy. Also there are 7 Dromore townlands in Co. Donegal, I did not find a Dromore in Taughboyne parish.
Roger