Ok, I've read Prime Directive D20, the Decipher Rules, the Last Unicorn Rules, and even the FASA rules - out of all of the the CODA (Decipher) System is the most detailed.
BUT (and there is always a but Lol) its not D20 - so where now. Take a backwards (IMHO) step away from DnD, or press onward.
Never having been the type to step away from a challenge, I shall be endeavouring to Convert the Races, Skill Programs, and even some equipment to the D20 system.
What will result will be a mish-mash of rules and systems that should 'fit' into DnD 3.5 (I've opted for 3.5 over 4e - 4e is much more heroic fantasy IMHO and less suited to the Universe of Star Trek. That MIGHT change as things get converted and written - if it turns out 4e is more suitable, then so be it!).
Another long put-off project will be updating all my old rules for AD&D 1st Edition, most of them center around Lemuria - the ancient continent that was the 'seat' of many of my Games. A Background that got perverted by another DM (including, but not in any order of absurdity - Daleks, an Alien Villain called 'Azra' and my personal favourite - the Horse Plague, which happened because he felt - "The player characters get around to quickly" - I kid you not Lol).
HOPEFULLY there won't be as long a gap before my next Post, if things get a little less hectic around her - but with being busy, helping my Dad (whos on his own now), a new Grandkid on the way, AND one of my Cats had Kittens - its been mental around here Lol!