I wrote some time ago a model exporter for 3ds max, and it works fine. Now I''m trying to export the vertex weights in order to animate the models in my engine, and here''s the problem: some some vertices have more than 2 weights! In my engine I use 2 weights per vertex, so the vertex can either have 1 or 2 weights, but if it is influenced by, say, three bones, I cannot export it properly (i cannot simply "cut" the third weight, because it will no more be balanced) So, is there a way in 3ds max to automatically limit every vertex of a mesh to have TWO bone influences? or do I have to manually check this before exporting? Thanks.

You can change the number of bone influences in the Advanced Parameters rollout of the Skin modifier panel. If you change the number after the skin has been applied, you might need to reset/redo the weights on the vertices.