Dear Sir,
This might indicate a communication problem between your KC705 and host computer. Please check CAREFULLY the FAQ (
http://www.4dsp.com/forum/index.php?action=faq)
It is generally because firewall (on the machine, or external setup by the IT dpt in your company), an antivirus like Avast or that KC705 has wrong Ethernet settings (KC705 switch configuration).
We also seen that because the PATH environment variable does not contain C:\Program Files (x86)\4dsp\4FM Core Development Kit\Bins and C:\Program Files (x86)\4dsp\FMC Board Support Package\Bins this happens.
About the crossover thing, I am not sure if the PHY on the KC705 supports lane reversing or not.
Please let me know which BSP version you are using, we recently fixed a PATH issue.
Best Regards,
Arnaud