I don't know of any, but if it is possible, some of the more tweak-savvy folks are sure to let you know. I do know that if it is possible, you are likely to also get other behavior that is not intended, since you will be modding the preset to be something that it is not. Which compressor are you trying to modify? Have you looked at other libraries that may be better suited to your needs as-is?
There's not much you can do with a finished preset. For the development of the KultComp i used a trick for extended times, but it had to be done at the sampling stage. As a result it has 0.1ms to 980ms attack and 0.03 seconds to 5 seconds release.
Thank you for the responses as that is what thought but just wanted to ask. The compressor I like to use on some masters is the AITB Fate as once in a while when working ITB it has a really nice vibe to it but feel the attack & release make it hard to use as a comp during mastering.
I might try the KultComp by Gemini as I liked to use the N**e on hip-hop/rnb masters to give them some weight.