Hi I am currently designing a rifle for poser and the market place. The modelling was done in max and then exported as an obj and imported into poser to texture and set-up. Since its my first model for poser I had to go back to max,tweak the original and export again into poser alot of times.

Just today I noticed that on one of the parts of the model there are 2 open edges and some dents.  On the original there is no open edge, I am sure of it. I re-imported the mesh into max to check if it was the exported file but the mesh was fine in max, but when I import into poser the open edge is always there. How do I fix this pls and how can I avoid such in future as I plan to go from prop designs to conforming clothing. I want to finish the model already :( Any help will be most welcome, and I will answer asap.

Are all your normals lined up or do you have some flipped backwards?  Also, are you leaving complex polygons for Poser to triangulate for you?

Could you post a wire-frame view of the offending parts? I suspect long, thin triangles which Poser doesn't handle well.

You should also avoid polygons with more than four sides as jentron says.