Creating Shadow LODs

1 - Open a 10000 distance view LOD (note it's 10000 not 10.000)

2 - Make the model to use as a shadow inside the 10000 LOD ( for example a weapon should be like 200/300 polys tops, of course the less the better).

PS: Don't forget to delete the textures applied on the Shadows model (if you have any) since it's all black you don't need it mapped.

3 - Open a property inside your 10000 Lod and call it Lodnoshadow the value is 0

4 - Open the same property (Lodnoshadow) in all the other Lods but this time give it a value of 1.

5 - Inside the Shadow Lod (10000) with the entire model selected go to Structure/Topology/Find non-Closed and check if you have any opened point/faces (they get red if you do and below on your left O2 tells you the amount of them).

6 - If you do have any opened points/faces you must close them, you may try O2 to close them for you, for that go to Structure/Topology/Close, this should close the model for you, however, sometimes you need to do it by hand since this feature inside O2 as some limitations.

PS: Be sure that all points/faces are closed, the best way to know this is by doing the step I wrote you before Structure/Topology/Find non-Closed and see if it gives you 0/0 on the left part below, if you miss this than not only the shadows won't work as most of the times the game will crash while loading the model.

7 - Finnaly with all points/faces closed, select the entire model and go to Structure/Triangulate \ .