I had checked openrave ikfast last week and it works well with our dual arm humanis robot, which I believe more complex than your robot.
Please follow followong discussion and lets try with nextage robot and see if your environment is correct.
What we have found is we can generate cop file but that is not compilable with default sympy 0.7.4 ship with ubuntu 14.04, and sympy 0.7.1 solves this problem. I expext since your robot is simpler than nextage, you can run with 0.7.4 sympy.
* simple/complex is not just a shape, but the configuration of joint where nextage does not have orthogonal axis in shoulder and wrist.
Also please check your openrave version. 0.0.4 may work, 0.0.5 is the latest production version.
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