 As master of work for Edinburgh burgh council, MacDowall measured quantities and made contracts with masons, including works at Newhaven.For St. Giles he procured timber for roofing the Consistory in 1555 and wainscot in 1557 for the seating of Our Lady's Aisle.After the death of Mary of Guise he remained in Edinburgh Castle and was charged with neglecting his duties as a warden and Master of St. Pauls Work, and after the reformation of 1560, MacDowall was excluded from the town works, which recommenced with the conversion of a part of St Giles Kirk into a new Tollbooth.