Thank you for all your comments guys it has been most useful.
I should have said that the two airfield terrain boards were ones we had privately made in order to display aircraft on at trade shows, they are not the ones we are going to make in our factory. If we go ahead and manufacture something like this then we will obviously make alterations and some improvements as suggested in the comments by forum members, which incidentally have been invaluable.
The FFL fort idea received a very healthy response and we will do some research on this and then let you know how we get on. Most people seemed to like the idea of a small Fortlet or fortified Desert Outpost rather than a large fort.
We have mulled over the idea of making the FFL series is a smaller scale in order that a larger fort could be made, but I am not sure this would be popular except if you were a new collector to the series!
Once again thank you for your responses, it took me an awful long time to work thru them all.
Best wishes Vicki