Well, I actually just got some mail that helped on the Mac front (from a "J Vulcan"). First, here is a patch that works with Multipatch on the Mac:
http://www.mediafire.com/download/88lak54m5db1u0y/rgc2eng_v14_mac.zip
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Next, here are some instructions if you would rather use Wineskin:
I made some instructions for Mac users specifically for patching this game (or any games) and might help people wanting to run other utilities that might be Windows only. Personally, I'm a bit uncomfortable with command line or virtual machines myself.
The utility linked in the patch's readme works fine using Wineskin.
Used Wineskin. It's a Wine wrapper and will create a complete executable (with Wine binary + utility) included to run like a near native package.
-Download Wineskin
-Install Engine
-Install Wrapper
-Create New Blank Wrapper
-It will create a blank wrapper in the /Users/[username]/Applications folder
(Wine Mono and Wine Gecko will be installed)
-Install Software -> Copy or Move the patching software folder.
It should run. Tiny window somewhere, usually upper left corner should appear. The wrapper should map OS X drive, so hitting "Desktop" when selecting a file should show the Mac desktop. Recommend that users just put the software there.
Success.
Note - (To access the settings and setup, users must right click the wrapper -> Show Package Contents -> and run the Wineskin.app again) ... This will show the virtual C: drive.
Note:
Users that want to remove the Wineskin Winery utility can either drop the applications into the Trash or use a free utility like App Cleaner. The /Users/[username]/Library folder is hidden but accessible by going into to Go -> Go to Folder from a blank desktop at the top of the screen. Users can simply search for Wine references and trash them.
The entire package is something over 400mb, so it's not feasible to redistribute. Compresses down to 173mb using standard ZIP. The entire thing would be safe to redistribute. Wineskin + the libraries are all LGPLv2 (or GPLv2).