Nick, your trn tutorial is very nice.I would only add that it can be helpful to intentionally (and temporarily) create an elevation mismatch (and a visible tear when slewing around) to serve as a visual reference point, as for example, when the ground tile indices alone are not precise enough to locate a spot for editing in a high detail grid. Oddly, tears from mismatched elevations on borders of supertiles (and high detail grids) in different gxx.trn don't show up when slewing around, but it is a good idea to make sure all elevations shared by these supertiles (and any high detail grids) match up as well.Speaking of tears, you occassionally see gaps (or tears) at seams of bordering high detail grids of different density (2x2 grid bordering 8x8 for example) even when all elevations in common between the two grids match perfectly. There are also some momentary gaps or tears that temporarily appear when flying towards seams between high detail grids, especially in rough terrain. Actually, I had been wanting to add my own high detail grids where none existed before. You have encouraged me to try this out when I get some time.

Guys:Just to note, when I created Dallas without DEMs, everything worked fine. And because the area is already pretty flat, no harm done on inaccurate elevations.Just wanted to update everyone.-DKPS: Nickster: I will check out your tutorial. Thanks for starting it!----David KohlFly! II v2.5.240Dell 8200 P4/1.8G, 1024MB RAM, Nvidia GF4 Ti4600 v41.09, WinXP Home Edition SP1.CH Pro Pedals and Yoke USB.