Page Design Element Questions

When adding the Marketplace grid to a page, I am running into two issues.

1. Is there a way to eliminate the extra space that is under each product listing? I have tried to add an excerpt but it didn't show up.
2. I have a line showing up at the top of the grid. Can this be elminated? I believe it has something to do with the fact that the grid is floating. Can you point me in the right direction re: code file.

Thanks for all your help.