Hmm actually I’ve just come across ‘Merge Actors’ command which does what I want so I can export that mesh fine, the only problem with that method though is I can’t find a way to keep the pivot in the merged actor at the centre of the actors I selected, I can only seem to keep the pivot from the first selected object or use the world 0.
My other thought was possibly using an empty actor in the scene as a fake root for the merged actors so the pivot would align to that allowing me to position the pivot manually.