Hello Diego,
Yes we landed on the same thing, Even I could not get the TLC5940 as it relies heavily on internal AVR registers.
WIth the PCA9858, I didn't know how to define "edison" in library, thanks to you now I know its __x86__ , So I took the dirty route and changed 27 line to #define WIRE Wire. I did not to modified the Arduino.h file and was able to compile the servo example , the pwm test example uses an internal register TWBR, so was not able to compile it, if commented out it works.
Since you getting the data stream, library is working.
I don't have a PCA9858 board as I'm short on deadline I could not wait for the parts to arrive, so I used the tools at hand.
Currently I'm sending data from edison using Serial, all the commands are stored in an array , on the slave side I'm using arduino mega adk and parsing the serial string and taking the appropriate action. When the command is executed on arduino board, it requests for next command and edison sends the next one and it keeps on looping.
Thank you for your time and effort.
--Regards
Hemal Chevli