>The trello thing is confusing me, there is no status if somebody has done something or if the attachment is from something they created or from the web etc.

The color will tell: red means "to do", yellow is work in progress, green is done.

>I guess I'll start with checking out the models you have already in the game and then just make some easy missing stuff from the classic clonk.

In general note that getting your graphics scripted from a programmer is only likely if you do communicate with him about the graphic. Doing 'just' what is obvious to someone might not always find backing from other people. Clonk is a pretty complex game with visions differing from person to person. I'm not exactly sure what easy missing stuff from the classic Clonk you are referring to, hm.. ah maybe some flints? But that's the only thing that comes to my mind.