Tip tranny fluid leak?
 

What are the signs that the tiptronic transmission fluid is low?

The reason I asked is because I noticed there is/was some kind of fluid/oil leak near the rear section (passed engine) but I can't tell whether it's engine oil or tranny fluid (brown color), driveway is dry for the past 2 weeks of ownership. Also, 2 days ago when I make a sharp left turn I noticed the RPM ramped up but car was at the same speed (tranny slip?). Other than that it shifts fine, I'm afraid to drive it much until it's checked out but in the meantime any idea what it could be? Thx for the help!