Yes, thanks very much.  I've changed the region to United Kingdom (which was one of the options in the box).  
But how do I delete the PLL_Narrow_Boat_50ft_Pottery?  I can't find it in the route (using Find Object).  Isn't that what missing dependencies means in the CM?  That it isn't installed?  So, how do I delete it from the route if it's not really in the route?  Do I just use the "Delete missing dependencies" option in the left hand menu?  
This is all pretty darned confusing!!