Hi Anthony
First off, let me say how pleased I was to see your earlies postings a few weeks back. I play an 804 and over several months of regular monitoring of this forum, you are the one and only other 804 player that has surfaced.
Regarding the .cst and .ast files for the KN7000, you will not be able to load those direct into the 804.
However, if you have access to a KN7000 or a friendly and helpful KN7000 owner/player (and I am told, that is the only kind there is) there is a way of getting those styles into the 804.
1. Load the .ast files into the KN's Custom Style Memory.
2. Copy styles one by one (maximum of three) from the Custom Style Memory into the Composer Memory.
3. Save the contents of the Composer Memory to a floppy.
4. You can load from the floppy into the 804's Composer Memory.

You will find that most of the KN7000 styles reproduce faithfully in the 804, the exception being those styles which contain sounds native to the KN7000 only.
Hope you find the above helpful.
Regards,
George