Hi DaveF, I have clarified and I am able to use OSM for mapping my data as OHM is not yet compatible with other software which I need to use. I am working with the Pleiades Gazetteer, the Institute of Classical Studies and the Roman Society to create a map of Aquae Sulis using Archeological journals and existing maps. OSM has been used for similar ancient cities in other locations and there have been no issues raised. I will see to NDM's problems. Thanks.

Hi DaveF,

Thank you for pointing this out to me. I have tried using OHM but the website seems down at the moment. Do you know anything about this?