Your report strongly suggests that you need to consider moving the antenna outside.
Though the CM-4228HD claims some H-VHF capability, I would expect the edge path conditions and wide separation between the main group of UHF only signals and the two H-VHF signals will force you to add a cut-for-band H-VHF antenna aimed at real CH-8 & CH-10. It's easy to combine the UHF antenna and H-VHF using the TVPRAMP1R.
Consider testing reception with just the 4228 outdoors, using this technique:
http://forum.tvfool.com/showthread.php?t=13646
If you can't find a compromise aim point that provides acceptable reception, get an Antennacraft Y10713 (A Y5713 may work. But the edge path conditions make me favor the larger antenna.) Rerun the test using only the H-VHF antenna, optimizing aim for CH-8 & CH-10. Then go back to the 4228 and fine tune aim for the UHF only signals grouped at 144°. When finished optimizing the individual antennas, I expect you'll be able to add the TVPRAMP1R into the system and have much improved reception.