Background and text look okay, but you just placed the render there without any blending, try out some tutorials on this site and you will get better.
Hmm, it's not bad. Although the render needs to be blended in some more, and remove the text or make it smaller so it's not so obvious. Effects are nice though. Read up on some tutorials if you haven't already for some tips n' tricks Good job.
it needs a lot more work, continue to read some tutorials and looking at other peoples work so you can get a feel for some techniques and effects. keep working at it.
If this is your first "good" sig, I'd hate to see what your bad ones looked like. Work on the text and look up some tutorials. It takes practice.
are there some tuts you would recommend?? btw, the background is almost brushed, didnt do anything else but a disort filter