I think you should be able to synch cakewalk with the Yamaha using MTC & MMC (MIDI Time Code & MIDI Machine Control). This is a method of syching machines which just uses one MIDI cable.
I don't know if Cakewalk can use MTC & MMC, but it seems like something it should be able to do.
Say you're recording a track into Cakewalk, you connect the MTC out on the AW4416 (if I recall, the AW4416 has a MIDI output connector especially for MTC) to whatever MIDI input you have on your computer. You then need to set the AW4416 as a synch master, and tell it to transmit MTC & MMC information (it'll be in the manual). You also need to tell Cakewalk to be the slave.
The idea is, that the two devices sync on recording and playback using the MTC - and the MMC information sent down the MIDI cable means you can start the AW4416 playing, and Cakewalk will automatically start playing/recording.
As for actually transferring the audio - that'll depend on what kind of inputs your sound card has.
I've never done this with Cakewalk, but I have used this technique to transfer audio from an AW4416 to
my Roland VS2480, and it worked fine.