Somebody has sent me a project folder which contains one huge survey (6k+) made with Pocket Topo. It seems they had only partial knowledge on how to survey a cave of this size and only limited experience of Therion so the whole thing is a bit weird. I said I would attempt to sort it out. Andrew fixed one issue with the data which has moved us forward but my question now is how to proceed. If I compile I can get .3d and .lox output which seems to work fine but the pdf output fails with a load of complaints. Looks like a size thing to me but having never seen this before I'm not sure. To me the survey needs breaking up but again I am not sure of the best way to do this, can some of you clever chaps have a look and possibly offer advise please. Be warned the th2 is difficult to handle my machine takes 3-4 mins just to load it and 2mins to refresh if I adjust the zoom. The guys who collected the data spent an awful long time doing so and are obviously keen to use this data as redoing the survey is not an option. It is quite an interesting problem and a very good example of how not to do things. Any comments or involvement would be appreciated. Nick