Thank you for your responses so far, I'm still having problems.

When I click on the about tab it tells me its "Gamestudio Extra 7.86 / WED V6.944"

Im reasoanbly sure I have A7, so the A6 map entity possibility may be worth investigating.

Ive tried experimenting with the "build map" options in the hope that this would resolve any issues, but I still have the same problem.