I buy old quilt tops and they are filthy. I pretreat the really bad stains with oxyclean or whatever I have and then I rinse the dirt out. I do not agitate the tops yet. Sometimes I have to rinse the quilt tops 4 or 5 times until the water runs clean and then I use my laundry detergent on gentle. I have taken baking soda and used that in a paste on bad stains, rubbing it with my fingertip. I use everything that I can to get them sparkling clean. I have to cut the threads afterward because they do become a mess. I would say almost all of the quilt tops are really good afterward, a few did not survive because they were such a disaster. I doubt yours are like that. All the blue marks from the embroidery guides will disappear when you wash your quilts, I have some of those too and they came really clean. Good Luck.