Sorry, not much help here- but I agree that color/greyscale tuning can be difficult without the right equipment. Pros use tools to fine tune the greyscale. It may not be worth changing these settings if you aren't sure what you are doing.
I do know of a user on AVSforum.com that has calibrated Optoma projectors for $150. His user name on AVS is guitarman and his name is Tom. He did my Optoma H77. You ship him your projector and he turns it around back to you within 2 or 3 days.
Someone else may be able to give you more information on how to attempt this yourself.
