I am not getting that here. Please post back your Bat version, operating system and Screen resolution you are using
The only thing I can think of is highlighting the green lines and  see if there are while letters on a while background in there for som ereason.
If you can take a screen shot that might help

Find a place to host your image (imgur, photobucket, flickr, etc). Then write your message here and click the little landscape icon above the editor to link to your image file.

I don't get those green lines, but I still use a very old version of The Bat. At first sight, they look like page separators (they might indicate the page length at the current printer settings) - but that is just a guess.