Thanks for expanding your interest. I cant guide you to church records further, except to ask did you search the Cof I records in Newtownards, as well as the other presbyterian churches in the parish. Then I wondered about farmers who stay for many generations. {The Gunnings at Drumawhey in Newtownards had caught my attention.} Then I spotted a Gunning Whitla marriage in Newtownards. I have a Gracey Whitla/Whitley connection in Comber and Newtownards. I will check out my limited Whilta research and come back to you.
Have you looked at Genes Reunited if you are not a member, There are 18 matches for Gunning in Co Down before 1838. one or more of these tree owners might have uncovered some data related or unrelated to your line
Have you tried the free index for
http://www.ancestryireland.com/ It has a Samuel son of James born Co Antrim1820 they also mention 5 entries in the Index to 1796 Flaxgrowers Bounty List, which I looked up elsewhere but no Gunning in Co Antrim or Down.
The same applies to
http://titheapplotmentbooks.nationalarchives.ie. It widens the search using the variant Guning. {I am uncertain about the Tithes for Co Down being complete}
Using
www.lennonwylie.co.ukIn 1820 Custom House Quay Daniel Gunning, Clerk of Permits [Included because it’s a unique job}.
In 1843 There is a Gunning cabinet maker in Donaghadee but no Gunning in Newtownards
In 1852 there is a Robert Gunning living in Craigavad in Holywood parish
Have you tried the local history unit in the Library section of the SE Education and library Board Ballynahinch who are developing an index to Co Down journals and newspapers.
I wanted to get a feel of the distribution of the name so I used Griffiths valuation about 1860s which I am sure you know about, and found these parish locations for Gunning, so although scattered and not focused into one small area, the majority live around the Ards peninsula, all of which means to me they have probably lived there from before 1700.
ARDQUIN, BALLYPHILIP, BANGOR, CASTLEBOY, COMBER [I have encountered some references posted as Newtown Ards District], DONAGHADEE, GREY ABBEY, HOLYWOOD
MAGHERADROOL, NEWTOWN ARDS [I have encountered Donaghadee items posted as within Newtownards district. But not the reverse ]. SAINTFIELD
They also leased property in ARDQUIN, BALLYPHILIP, DONAGHADEE, HOLYWOOD
and MAGHERADROOL. Showing the family surname was more successful than many others
While I am in Griffiths the map section would show the homesteads boundaries. This is based upon the 1st rev of the 1st edition of the OS about 1860s, but the 1st edition 1830ish exists . Copy of town lands in SE library at Ballynahinch
In 1876 Landowners of Ireland, James was the only Gunning landowner in Co Down listed at Ballygrainey which is either in Bangor or Holywood civil parishes
PRONI has Probate of the Will of Eleanor Mary Gunning late of Drumawhey County Down Spinster who died 19 June 1904 granted at Belfast to Andrew Gunning Grocer etc Another will refers to a Gunning living in Balliggan Balliggin Inishargy 21; 62/65 4km SW of Ballywalter; I stopped looking therafter
So that’s my contribution apart from the Whitlal/Whitley marriage which if I find I will come back to you. Lets hope you break through the brickwalls
JimG