Hello @DjangoTango, thank you for your response. For the DYNAMIXEL MX-series, I would recommend starting with an example such as “read_write” under which can be found under File>Preferences>OpenCR1.0>07. DYNAMIXEL SDK> protocol1.0> read_write.
I would not recommend starting with examples from DYNAMIXEL Workbench before becoming more familiar with available settings for your model of DYNAMIXEL. The j_current_based_position example is used with models that offer Current-based Position Control Mode, which is not available by default on MX-64 (but may be unlocked later with firmware upgrade).
For more information on matching examples to your model of DYNAMIXEL I might recommend our FAQ section here as well as this video from our YouTube channel.
Let me know if this helps or if you have additional questions!