You should get HDMI audio on the K2000 with layout #3 or #7. I was able to get audio passthrough on DP without any specific configuration changes. Do you have a converter inline? Which DP version are the cables? Does it work on any of the ports?
Did you generate an SSDT for CPU power management using
pikeralpha's tool? If you're using my EFI you'll need to generate PM info for your processor (unless you have the same one, which I doubt since I had an oddball CPU). A patched DSDT can handle those things as well as your USB and sleep issues. Are you still using NullCPUPowerManagement.kext? I improved things stability-wise when I got rid of that.