Can I use styles created on RMCA in Korg IX 300

I don't think so, it uses some own incompatible format, but to be sure better ask the author directly.

There is a Korg i-Style converter from midi files that works with ix300 and all other i-series Keyboards/Modules.
It is called GNIStyle Shareware
more info at http://www.iicm.edu/Cpub

With the demo you can already create a small style and test it on your keyboard.
It is not expensive and can be ordered at http://www.regsoft.com

Guenter