Post Separator transparency not working? How to split posts?

[alex3003]

Hi all, I'm trying to split the user posts by about 10px. I have a pattern background underneath which is fixed. The transparency for Post Splitter doesn't work.

I tried this tutorial here: forum.sz-ex.com/thread/16461/post-splitter
But it didn't work: the gaps were too large even after removing the br tag, and also, there were large green bars at the top of every post.

Thanks in advance!