Eizo is free but it will work only with Eizo monitors.
For Eizo better to have X-Rite Display Pro than Spyder since Eizo color accuracy is better than Spyder’s accuracy.
Ask for Eizo representative in your country to provide you the link to CN7.
RH is only supported by Eizo but…
For CN6 I just looked at the instalation scripts and mimic what they did. Some libs here, there. Nothing special. However better to just have CentOS 7 in VM for that. You got one problem less.