Try calling the manufacturer or the installer, if that doesn't work for you then you might want to try Turpentine. Try a little on an inconspicuous place first to make sure it won't make the situation worse. Blot, don't scrub. Get out the turpentine with a mild soap and water solution.
KBonelli - hi, the big box stores carry a product called "Goof Off" that may work. I haven't looked at it closely to see where it can be used or any items it won't work on. If you're going by one of the stores, it may be worth the 5-10 minutes it takes to stop in. The product should be over in the aisle for cleaning solutions although it could be near the paint section.
TPerez - I don't know if you're active duty, reserve, or have a relative in the Corps. Regardless, thanks for serving/supporting the troops. My career's winding down and the young kids make me proud to have served this long! Regards and Happy Holidays! Jim D/West Point, VA (USAF active duty CMSgt [E-9] with over 30 years in...voluntarily stayed beyond mandatory retirement at the request of the commanding general I work for...stationed at Andrews AFB, MD)