Congratulations on your recent purchase. I, too, have recently acquired a Dolphin. It looks like you have the same issue as I do.
There are a couple of options for cleaning up the putty which has seeped out of the mating surfaces around your windows and doors. Which one you choose depends on how much work you're willing/able to put into the clean up project. The putty that makes the seal is a butyl tape that does not cure. It provides many advantages for sealing these coaches, but the downside is that it will slowly seep out and collect dirt and grime.
The first option is the quick and dirty approach. Since the butyl putty tape does not cure, you can scrape away the excess without damaging your seal. Use a plastic putty knife so that you don't damage the enamal finish on your coach and then clean up any remaining residue with a little turpentine. To keep a nice clean look, you can then add a bead of 100% silicone caulk. Make sure sure to use silicone and not latex and be sure to wash the area with soap and water before adding the silicone since the turpetine leaves a residue that the silicone won't like to stick to.
The second option takes a little more work, but it well worth it in the long run. This involves actually removing the windows and door frame, removing the old butyl putty and replacing it with new. Rolls of 1" butyl putty tape (20 ft long) are available at most RV supply and hardware stores for about $5 a roll. The process involves removing the screws from the frames (the window frames come of from the inside), pulling them off of the coach (be careful not to bend them) and scraping away all of the old putty from both the coach and the frame. Apply a new strip of putty the the inside surface of the frame and then remount to the coach. If any of the screws you remove are rusty along the threds, you may have to reinforce the screw hole in order to get a good tight fit. This can be done by dipping hard wood toothpicks (the round kind are best) and a little carpenters glue. Make sure your frame is good and tight. It is best to alternate from side to side when putting the screws back so that you get an even fit. Once it's all back together, trim any putty that seeped out beyond the frame with a plastic putty knife. Then you can apply a bead of silicone caulk to maintain that clean look.
Hope this helps. Good luck.
