I have upgraded my network monitoring setup to use OpenMotes, as you can see in the photo below.
I only had to recompile the OpenWSN firmware with the proper board and toolchain parameters:
scons board=cc2538 toolchain=armgcc oos_openwsn
OpenMotes require use of a Segger J-Link to flash the program code. I followed the instructions on the OpenWSN wiki. The J-Link will be valuable for debugging, but I also look forward to flashing directly via USB with the cc2538-bsl utility.
I was able to run my network monitoring demo of RSS reporting using this setup. I found the Toggle button to establish the DAGroot on the OpenVisualizer web app less reliable with OpenMotes than with TelosB. However, once the network was established, it worked as expected.
I was surprised to see a signal strength of -69 dBm with a pair of motes only 25 cm apart. I would have expected at least another 10 dB, even with the stubby antennas. I plan to contact the OpenMote developers for their experience.
[Update 2014-09-29: As described in a follow-up post, one of the motes was faulty. With a free replacement from the OpenMote team, the signal strength is around -40 dBm.]
At any rate, we now have the infrastructure to start development of CoAP-based RESTCONF monitoring. I may work a little more on OpenMote setup, but then it's time for some prototyping and design.