Intel HD 4000 EDID Override for audio passthrough?

Wow! I was two seconds from giving up when I ran across a couple of threads on here about EDID overrides. I also found at least one instance of the new HD4000 chip allowing them, which is pretty exciting. I'm really hoping that one of you might be able to help me with an issue I'm having.

So here's my problem - I have an LG 42LD520 TV, and the EDID says that it only accepts 2 channels. In reality, it can pass through DTS and DD signals and does so all the time. Unfortunately, I'm not even given the option of trying it. My receiver is an Onkyo from the pre-HDMI days and replacing it isn't really an option.

Unfortunately, I can't seem to get EDID manager to let me alter the lines that should hold the audio capability information - gives me the error "DI-EXT Extension Block translation is not supported at this time." I'm pretty sure I'm just not extracting it properly - I've been having a lot of trouble finding a program that can do it. Does anyone have a copy of this EDID so I could try to alter it, or does anyone have any suggestions? Would really love to be able to use my setup the way it was intended.

Thanks for your help!

Okay, so I kind of got a little bit farther in the process and properly loaded the EDID into EDID Manager. Now instead of that weird error, it simply says that Block 1 is blank... is that better, maybe?