Hmmm... MoI does write smoothing group information to the OBJ file which probably Silo does not write.

Maybe Wings is not handling that smoothing group data well.

Those are lines in the .obj file that start with s, like:

s 1

Does Wings crash on you even with a very simple file like one box?

If so then we can probably figure out what thing Wings does not like by comparing the OBJ file from MoI with the OBJ exported from Silo to see what is different.

If you could post those 2 OBJ files here I could take a look at them to try and figure out what part Wings does not like.

- Michael