PEC_NORTH/SOUTH Clustering Guidance Needed

I have been trying to get two (then more) Parallellas communicating via PEC_NORTH/PEC_SOUTH for some time, but keep hitting roadblocks. I am using the Porcupine boards with ribbon cables. The first hurdle is changing one of the Epiphany ROW/COL to (36,8).
I have edited the platform.hdf and changed CHIP_ROW to 36.
I have a jumper on the Porcupine, pulling YID0 up to 1.8V.
After reboot, running any software that accesses the Epiphany gives me:
e_open(): ECORE[0,0] MEM mmap failure.
And then a segmentation fault.
According to this thread (https://parallella.org/forums/viewtopic.php?f=23&t=3659), this combo has worked in the past. However their code does not run on the latest SDK. Any ideas out there?
I have edited the platform.hdf and changed CHIP_ROW to 36.
I have a jumper on the Porcupine, pulling YID0 up to 1.8V.
After reboot, running any software that accesses the Epiphany gives me:
e_open(): ECORE[0,0] MEM mmap failure.
And then a segmentation fault.
According to this thread (https://parallella.org/forums/viewtopic.php?f=23&t=3659), this combo has worked in the past. However their code does not run on the latest SDK. Any ideas out there?