John Downey (1795-1850) and Bridget Mooney (1805-1865) in Bally Castle 1826 - 1831?

I'm seeking information about my 3rd great-grandparents:
John Downey
born abt 1795, Balinasloe, Galway
died 20 January 1850, Hulme, Lancashire, England
Bridget Mooney
born in Ireland about 1805 according to 1841, 1851, and 1861 English census but her death certifcate age indicates she was born in 1812.
died 4 August 1865, Hulme, Lancashire, England
John's British Army service record indicates that when he was discharged with pension in June 1826 he had a wife and was planning to reside in "Bally Castle, County Antrim".
Civil records in England indicate John and Bridget had two children born in Ireland:
William born about 1829 and Mary born about 1831.
Were William and Mary born in Bally Castle?
Was Bridget from Antrim?
Did John Downey serve at the Army Detachment in Bally Castle and meet Bridget there? Were they married in Bally Castle?
From his army record he served with a Capt Hill and Lieutenant Myland at "Mullenford [or Mullenjed?]". Is there such a place near Bally Castle? I've uploaded a transcript and inserted the image refering to this place.
Their daughter Jane (1845-1906) was married to Peter Connor at St. Wilfred's Roman Catholic Chapel in Hulme, Lancashire on 21 April 1866. Jane and Peter emigrated to Fall River, Massachusetts in 1883.
Thanks in advance for any help.
Chris O'Connor
