No worries if you can't find it there, just go here: http://www.amazon.com/KRUD-KUTTER-RC32-Remover-32-Ounce/dp/B000RUEE3M/ref=sr_1_1?ie=UTF8&s=hi&qid=1267501991&sr=8-1 (There's a description of what to use it on) I've used it on just about everything that had a clay stain on it, from concrete garage floor, basement utility concrete floor, stucco, fiberglass, cotton socks, teeshirts (yard work) and tennis shoes. ( Rinse it out of your clothes before adding it to a front loader!) Oh, I also got some clay out of carpet. It says its colorfast... Our stucco wall that was terribly stained and we cleaned all the clay off before painting. It worked beautifully! I don't have linoleum so I haven't tried that, but the description says it works on linoleum. I also go through gallons of the regular krud kutter....love the stuff! Good luck!!

Try white vinegar on a soft cloth. I used it to remove latex paint drips after I pained my kitchen. I have fairly new Marmoleum linoleum. I rubbed just enough to soften the paint, then picked it off with a fingernail. The shine on the linoleum stayed fine. Took a little elbow grease but it got the paint off. Not sure this would work on wood stain. Good Luck.

The best stuff I've found for this is 3M "Trouble Shooter". It's a commercial product, so you have to go to a janitorial supply to get it.. I've only seen it online by the case. Cost me $10 for a single spray can of the stuff, but that was more than enough to do my whole kitchen floor.. and it melted right through the 20 years of black greasy crud gluing my old stove to the floor. You spray on, wait 10 minutes, and scrub off with a plastic scrubber pad (I used the back of an old dish sponge) and lots of water, then mop clean. MSDS doesn't appear to call for a respirator, though I wear gloves and goggles whenever I'm scrubbing stuff. If you can't find that stuff easily, I'd do full-strength Simple Green and a scrub pad. That *should* pull the old crud off.. if it won't either then you will need a heavy-duty floor stripper. I'd want to try some more options that won't take all the "no-wax" finish off first, though.

Sooz, click flooring is not "waterproof". The surface of each plank, and the substrate in the body of the plank and click mechanism are waterproof. But you are correct, some moisture can leak down through the click mechanism especially if you flood the floor (wet mopping etc). But it's a very small amount and I wouldn't think it would damage the underlying subfloor. My concern would be the development of mold, or smell if it's pet urine flooding the floor! The benefit to that kind of floor is it's a bit more forgiving of a slightly rough or unlevel subfloor (sheet flooring is thinner and will transmit subfloor flaws) and it's warmer underfoot because it's thicker. It also can be popped up, cleaned and dried, and reinstalled if you have a major flood problem (sewage backup for example). If you don't anticipate numerous pet accidents or flooding consider a good quality click vinyl such as Coretec. There are numerous Coretec threads on houzz. And they do have tile look options.