Thanks to all who offered advice, but I'm still seeing the same problems. Those of you who have Paragon Chat working on a Mac, what apps do you have installed? Island Rum by itself will not create a usable application when run from scratch, as detailed below, so I'd like to know what success should look like.
I deleted the previous Resurgence that I'd downloaded, created a folder "City of Heroes" in /Applications, ran Island Rum, and pointed it at the folder I'd just created. IR first downloaded macclient.zip and extracted that, then began downloading files. It died once or twice, but relaunching it made it continue the download, until it finished. When done, the contents of the City of Heroes folder were:
__MACOSX/City of Heroes Resurgence.app, which was entirely blank
City of Heroes Resurgence.app, which contained all the usual application stuff, but not the downloaded data files
Titan Icon.app, which contained only Contents/Resources/transgaming/c_drive/coh/ with all the downloaded files
Attempting to launch either Paragon Chat or Icon from IR just made IR quit without launching anything else. I copied the application stuff from City of Heroes Resurgence to Titan Icon. I can now launch Icon successfully and get to the costume creator. The app that launches is Titan Icon, though it identifies itself as City of Heroes Resurgence in the application menu and in the list of running programs. I threw away the City of Heroes Resurgence app (without any data files), and I can still launch Icon.
I tried launching Paragon Chat. Little Snitch reported that it tried to connect to chat.cohtitan.com port 90. I allowed that, then got the same thing I'd seen before: the app is running (Titan Icon, calling itself City of Heroes Resurgence), but it has no open windows. Process Monitor shows that it's not entirely idle, using about 1.5% CPU. The menus respond (the "About" item works, though weirdly each time I select it the window is about 40 pixels shorter until it never appears at all), and I can quit the app, but that's all.
Island Rum's unzipping seems to have a problem. I started over and this time duplicated macclient.zip before IR deleted it. I unzipped it with The Unarchiver, and I got only the no-data City of Heroes Resurgence application, with no __MACOSX folder.
I noticed that Island Rum unzips the client, but then creates the Titan Icon.app folder where it puts all the downloaded data. Did a previous version use the City of Heroes Resurgence application name, and macclient.zip wasn't updated when it started using Titan Icon as the app name instead?
