Hi Tang,
Sorry I never got back to you on this. The current release of OpenMC (0.10.0) expects a v1 data library. The most recent development version expects a v2 data library. So, you just need to make sure that the version of the data library matches the version of the code you are using.
For the second problem, that is not really an OpenMC issue but a Python issue in general. That happens when you are trying to install the Python API into a location which Python doesn’t really know about. I would generally recommend installing the Python API into a Python virtual environment. To install the Python API from source, the recommended way is to activate whatever virtual environment you want to use and then run ‘pip install .’ from the OpenMC root directory. More information on that here:
https://openmc.readthedocs.io/en/latest/usersguide/install.html#installing-python-api
Best regards,
Paul