yes it's odd bug :)
But seems there is in general another solution for have the same result by a another way :)

On another subject: about http://moi3d.com/forum/index.php?webtag=MOI&msg=582.17
> Fillets block on construction line!
Yes, this is a limitation of the current fillet engine. Fillets won't cross an edge boundary like this. I hope that this will be improved in future versions of the geometry library that I am using

Does any chance you find new fillet library for the V1?