In your recovery, before you try to install the ROM, in the "install zip from sd card option" scroll down to "toggle signature verification" select it (this will give you an enabled msg). Then scroll back down and select it again (this will give you a disabled msg). Now continue with the ROM install.
If this doesn't work let me know.
If it is still impossible to deal with and you a forced to uninstall it let me know.

The Dev who has ported it to our phone doesn't seem to have enough time to work on bug fixes that much. I have been thinking about pulling it from the ATR Guide until it becomes a more usable ROM.

Please let me know how it goes.