Hi Brian
There are 43 parishes in County Tyrone. You can identify the civil parish of Dromore, and its associated townlands, at
https://www.johngrenham.com/places/civil_index.php by selecting Tyrone on the map. To gain insight into the economic and social landscape of 19th century Ireland you can consult A Topographical Dictionary of Ireland, published in 1837, by Samuel Lewis. Arranged in alphabetical order by place this dictionary provides an overview of the geography and history of Ireland’s villages, parishes and towns, as they existed at the time of publication (1837). The entry for Dromore can be viewed at:
https://www.libraryireland.com/topog/D/Dromore-Omagh-Tyrone.php .
Two townlands spelt on maps today as Drumaran are recorded in County Fermamagh in parishes of Cleenish and Derryvullan. The parish of Dromore in County Tyrone is bounded to the west by the parish of Derryvullan in County Fermanagh.
To examine historic maps and aerial photograph of Drumaran in Derryvullan parish, for example, search Public Record Office of Northern Ireland’s Historical Map viewer at
https://www.nidirect.gov.uk/services/search-proni-historical-maps-viewer. By entering ‘Drumaran (Derryvullan)’ in ‘Type Placename or Address’ box you will be able to view, by selecting 'Layer List' tab, first edition (1832-1846), second edition (1846-1862) and third edition (1900-1907) Ordnance Survey maps of Drumaran.
I must admit I haven’t heard of the term Conventioneers. I have heard of the term Convenanter, referring to Presbyterian settlers, with roots in Scotland, who migrated from northern Ireland to North America through the 18th century.