Foren / Cotonti / Support / Markitup error

Thanks Koradhil, I think that my problem is THIS.
I've installed on my web site a easyslider1.7 and I made a second css addition to the main "belagio.css"
if I delete this file ( slider.css ) MarkItUp back up and running.

I like this plugin and I would take on my site...any ideas ???

Added 15 days later:

nothing ?