I've been doing some maps of my own in Half-life; Deus Ex; and of course UT. The thing is I'm also "playing around with their window interface. I would change the look at start up; I would change the names of the menus...edit scripts/codes; I practically customize the look of the game in my own image and likeness...
Am I in big trouble?
Am I violating anything by doing this? I'm also planning of releasing these MODS commercially. What would be the implications of my actions?
If I will need to license it, how much would it cost me? What would be the terms and conditions?
Hope you could help me with my questions.
Thanks in advance

Am I in big trouble?
Am I violating anything by doing this? I'm also planning of releasing these MODS commercially. What would be the implications of my actions?
If I will need to license it, how much would it cost me? What would be the terms and conditions?
Hope you could help me with my questions.
Thanks in advance