Have you tried a good liquid dishwashing soap mixed with water. Possibly something like Dawn which should cut the grease. Be Careful...just use a towel or paper towel that is only somewhat moist. The last thing you want it getting water into the system. I agree that the alcohol may damage the paint finish.

Thank you for your response, sadly I tried that with no result at all. I even started doing it "less carefully" and it still had not effect at all.

Did you ever remedy this? Having the same problem

Yeah so, I contacted them again (been a while already) and they just sent a guy to my place (for free) to change the case from the laptop. I changed it to black to avoid it getting dirty as fast, and I do recommend that change. Regardless, they did tell me that they have a new material that makes it harder to get dirty and well.. it is somewhat true. Partially works, just do clean it regularly else its gonna be the same.

I appreciate the response. I also contacted them and they are sending a technician over to replace the palm rest as well. I was relieved that Dell was ready and willing to replace it free of charge and without putting up a fight about it (Thank you Dell and Alienware, I was pleasantly surprised) ... I am going to grab a d-brand skin so this won't happen again.

So there is a way to remove the stain but it removes the clearcoat covering (voiding the warranty) so I wouldn't recommend it.

That used nail polish remover (voiding the warranty) but the only real way is to upgrade to the m17 R3 and M15 R3 shells for the casing as I've personally experimented with the shell coverings on the R2 and R3 models and found out the newer ones are much harder to get darker or yellowish stains on because they fixed the clear coat issue.

The same applies to the black panel for the R2 as it also stains pretty badly after a while like the lunar white but if you have the R3 no worries.