Well then, I misunderstood your reply.
What you and other will find: There is no infinite backwards compatibility with older browsers. The only way that could be accomplished is by design to older standards - dull .js, no swf, etc. That also includes designing to standards that are not compliant with today's Web standards. To see what I mean take a visit to
http://validator.w3.org/ with an IE6/7 compatible page (without the "if IE 6 or if IE 7" embedded).
I can fully understand that some users might need to rely on older IE versions for older custom made apps that might be used in an internal environment - but to use a browser that poses a security risk externally? In my opinion is that is negligent.
As someone who tries to make my own "custom theme" for CPG and who has tried to make a few plugins I can say that the old IE has wasted hours of my time and that I am just about done with it. What should I do? Also make pages that work with IE5? If my visitors can't upgrade to a free, modern browser then I have to say at some point in time..... "Upgrade or too bad for you".
As web designers if we keep encouraging the use of out-of-date technology then people and MS just won't do what is right and get into the current era.
I hope you have read the warnings in the link I had attached - all you need to do with IE6/7 is click on a "bad link" and someone can execute code on your machine. Be careful. On my cpg1.5.x I a try to discourage people from using IE6/7. (click the link below to see) I wish others would do the same.
Yes, there are some experts in this forum doing what you are trying to do - maybe they can help.
Apologies for misunderstanding in the first place.