One of the final problems to be resolved in my mac-inating my MSI Wind / Advent 4211 was that although the Realtek ethernet adapter showed up in the Network control panel. its status was always 'Not Connected', even though the cable is known to be good.
After investigation it turns out that the issue is an auto-negotiation error. To fix I clicked on the ethernet adapter, selected 'advanced' and then the 'ethernet' tab. I changed 'automatically' to 'manual', and then went to the lowest common denominator which is 10baseT and half-duplex.
Click OK and the apply, and it connected and got an IP. From there I worked through the various ethernet combinations.