I've been looking and looking for help in planning our daily itinerary to DL in July and can't seem to find anything out there since I am a Mac user. Are there any suggestions?
You aren't going to find anything like RideMax for the Mac. Your best bet is to buy something like Sehlinger's Unofficial Guide to DLR which discusses which rides have the longest lines and has several sample itineraries.
I'm a mac user and downloaded the program to use at a friends' house (pc user). I took a couple evenings and ran all my touring plans. A little inconvenient, but in the long run I am still glad I used it.