Just to revisit this topic a bit: I did try running Harpoon in Wineskin on my Mac, but the graphic glitch, and the issues with the scenario editor pretty much killed it for me. The GE runs perfectly aside from the graphic issues, though. I did get a few other games to run perfectly in Wineskin, though. Good enough to go out to gog.com and get the 'complete' installers with all the expansions cheap, and install them in Wineskin wrappers. A couple of them even run better under Wineskin than the Mac ports did.
What I do now, and will continue to do, is run HCE in a Windows XP VM under VirtualBox. Everything works perfectly, including the scenario editor, and I can even run it in 'Seamless Mode' which puts the windows directly on my Mac desktop. No 64-bit problems like with Windows 7. As far as security issues with end-of-life XP, I just turned off the network card for the VM, and move files to it with a shared folder capablilty built into VirtualBox.
However, I will most likely try installing H3 in a skin at some point, and see how it does, though. It shouldn't have the same issues, since it's newer.