I solved the background issue.
open the styles. css (modules/mod_s5_tab_show/s5_tab_show/styles.css)
find this:
#s5_button {
position: relative; /* important */
overflow: hidden;
margin: 0;
z-index:1;
background: #fff;
and edit color to your needs.
You will then have to edit the tab_show "png" files to your needs.
The truncating is not that bad, I guess I can live with it for now