Maxium have one FM transimitter device. Lot of FM transimision module use this design.
check this link.
http://electronics-diy.com/Single_Chip_FM_Transmitter.php
256pins SMD component? what is package type? QFP? You can try, but if you are not experienced man, you will give up...
You might need to read something about high speed digital design before you start you PCB tracking. Impedence control, ground bounding, cross talk, signal integrity. A lot of...