-Redacted-
I think ripping off sprites or backgrounds 1:1 is a problem, otherwise good luck with it.
May I ask what platform/engine you are using (GM, XNA, Unity.. )?
I can change the Stickman, but it's a bit too generic to be a big deal, I could recreate my own and chances are it would be exactly the same thing.
I started off using LWJGL but then I got lazy and ported to GM.
Pretty sure using the stickman isn't hurting anyone. As long as you give credit to where credit is due you should be fine. I think the only scenario that it would be really bad would be if you were making profits of this game.
Good luck on this project!
I would like to be introduced to other people know about.