Hello great modding comunity! At first let me thank you for all your amazing work, which makes KSP such a great experience. It even inspired me to try to fabricate some own parts, but as you all already guessed, my enthusiasm and work were soon confronted with problem I am unable to solve alone. And thus I turn to you with plea for help. My vision is to create parts for construction of cargo (space)plane. I don't want animated cargo bay like space shuttle had, just cargo deck like transportation planes have. I am absolute begginer with almost no knoledge. But thankfully this forum and youtube is full of very helpful guides. I managed to model and export part into KSP, everything to my liking. But I don't know how to handle collider mesh for hollow object when it must be convex. I've tried three aproaches, but niether one works: 1. I made standard convex mesh collider and allowed collision in part.cfg. I still can't place stuff inside. 2. I made U shaped mesh collider for floor and sides (so I can attach wings), but Unity makes it full (convex), so it takes more than half of my cargo bay. 3. I made mesh collider just for floor part. It sort of "works" but I cant attach wings on side of plane, just on the lowest part where collider is. You can find very illustrative images of my problem in my dropbox here: https://www.dropbox.com/sh/6o7b4oquo0vgpqr/AAC9lK5V1NJGE2U67Q7m9j4Qa If someone of you would be so kind and explained me, how to make it functional and in correct way I would be very grateful. Jenda P.S.: Sorry for grammar and typos, English is not my native tongue.