I just had to deal with this problem in another project. This is probably a hardcoded path in on of the project.pbxproj file inside the xcode project.
Open up terminal and go the the root of your Ogre source tree. Use grep to find the file with the problem:
$ grep -R "steve" *
This will do a recursive search of the directory for the word steve. You may want to use "Shoggoth" instead if the first search doesn't narrow it down enough.
You should see the matching files with the filename, a colon, and then part of the matching line.
You can then use pico from shell to edit the file:
$ pico <filepath found by grep>
Use ctl+W to locate your search term and correct the path to the plist. There should be others in that file which will give you the right path prefix. Make your change and then ctrl+x to exit, press 'y' to save and enter to accept the filename.
Go back to xcode and try to build again.
If there are multiple deployment targets, you may need to correct the same problem again.
If you havn't figured this out already atorkhov, all you need to do is get info in Xcode on the OctreeZone plugin go to build tab scroll down to packaging section change the path for the feild info.plist File to ./plist/OctreeZone Plugin-Info.plist, just like the others.
