The architect James Salmon supervised the works and added a tower, and the church subsequently incorporated a major collection of Pre-Raphaelite stained glass windows.

[3] It was subsequently opened to the public on days when cruise ships called at Greenock, and Inverclyde Tourist Group provided guided visits with a talk on the history of the kirk, but with the onset of the COVID-19 pandemic tours became unavailable.

[6] At this time there is no record of any village; retainers and servants lived at the castles, while most of the inhabitants were fishing families in temporary huts in small straggling groups on the coast.

[7] There were a few chapels: one at Chapelton overlooking the Devol Burn, and St. Lawrence near Wester Greenock castle (at what later became the south-east corner of Virginia and Rue-end Streets).

[10] An early Church Commission later cited authorities including "Johne Craufurd of Kilburnie Johne Schawe of Greenok" and "Patrick Rae in Chapeltone" to support their assessment (in Scots miles) of the distance as "four large myles vith dyveris great burnes and watteris in the way quhill in the vinter sessone are vnpassable and the number of people many.

King James was "movit with the ernest zeill and grite affection our lovit Johnne schaw of grenok hes ay had to goddis glorie and propagatioun of the trew religioun", and approved the aim that the "puir pepill" dwelling upon his lands and heritage, who were "all fischers and of a ressounable nowmer, duelland four myles fra their parroche kirk, and having ane greit river to pas over to the samyn, May haif ane ease in winter seasoun".

The church windows were fitted with clear glass in small square panes, the walls were whitewashed inside, and it had a flat plaster ceiling.

In 1635, when the parish was extended to include the Easter Greenock lands of Crawfurd of Kilbirnie, the "Laird of Kilburnie" offered to enlarge the south aisle by 22 feet (6.7 m).

In 1674 Craufurd of Cartsburn offered to bear a proportion of the costs of enlarging the church with sufficient seats for his family and tenants, a new manse, and a school for "training up the young ones".

Adjacent to it, a gallery forming the family seat of the Crawfurds of Cartsburn was built against the north wall of their aisle, appearing rather like a four-poster bed.

The Schaw east aisle was fully taken up by Sir Michael's gallery which projected out from the wall and had two oak pillars and two pilasters holding up a canopy over something like three private boxes.

When Schaw's retiring room was converted into the vestry, it still had access only through the east aisle gallery, so the minister had to go outside, down the external stair and round to a ground floor door near the pulpit.

[22][18] Greenock was boosted by the construction of its harbour in 1710, and the growth of shipbuilding began when John Scott's started building fishing boats on the east bank of the West Burn a year later.

[2] The Kirkyard was expanded in 1657 and 1721 to provide increased graveyard space, but in 1773 a request for further extension was resisted due to pressure of demand for land in the town.

[34] The kirk obtained a major collection of Pre-Raphaelite stained glass windows through the efforts of Allan Park Paton, librarian of the Greenock Library, who consulted Dante Gabriel Rossetti,[35] and received a response from William Morris in February 1865.

It includes nearly thirty figures, with 16 biblical characters in four lights, under angels giving praise, and at the top of the arch the Lamb at the centre of emblems of the Four Evangelists.

[38] From 1711, John Scott began shipbuilding on the opposite bank of the Westburn, and from 1740 onwards shipyards increasingly encroached on the land between the Kirkyard and the Clyde.

[39] In 1917 Caird & Co. were taken over by Harland and Wolff, which proposed huge expansion of the shipyard, taking over several properties including the original harbour, the kirk and the kirkyard.

They offered generous compensation, including a new site about 0.5 miles (0.80 km) further west along the coast at the east end of Greenock's Esplanade, and agreed to have the kirk carefully taken down and re-erected.

The 1842 monument to her, designed by John Mossman, was moved from the old Kirkyard to Greenock Cemetery, and Mary's remains were re-interred under it on 13 November 1920 in a solemn ceremony.

[27] Harland and Wolff's contribution was organised by Lord Pirrie, and included provision of a new church hall on the new site, which would take the congregation during the works.

Five days after the church was closed for work to start, the Pirrie Hall named after him opened on 19 February 1925 and provided a temporary place of worship giving churchgoers the opportunity to watch progress on the replacement.