Oops, forgot to mention that I tried your suggestions but they didn't work. That's why I started exploring.
Signature Verification - it was off, but I turned it on and, when that install didn't work, I turned it off again and the install still didn't work. Tried it with the stock and modded alternate file. I also tried "toggle script asserts." Didn't work either way. Both system and data were unmounted. I mounted data, didn't work with either file. Then I also mounted system, so both were mounted. Neither file worked. Then I unmounted data, so only system was mounted - no joy with either. Then I unmounted system, so neither were mounted (the way I started), and tried again in case the mounting/unmounting shook something free but was still unsuccessful. As far as I can tell, I've tried every permutation of what you suggested.
If the data about the partitions isn't useful, please let me know and I'll drop trying to make this work on the Bean Whiz. I hope there are no hard feelings, and that I didn't screw something up that put you to unnecessary trouble!
However, in the process of monkeying around with two phone ROMs simultaneously while knowing nothing about what I'm doing I have botched something in my daily driver (the Mirage ROM), so I have to reinstall it again. Since I no longer have anything to lose, and the failures to install didn't do anything horrible to my Bean Whiz phone, I'm going to try that next (once Bean Whiz is off the table). I was hoping that I could install the Bean Whiz to my daily phone, which is why I've been testing it, but my workaround of downloading the apk, moving it to the phone with no space and installing it from the sd card didn't work as I'd hoped, so I really want your program to work!
Please let me know if there is anything I can do to help. Thanks for all your effort on this idea!