Yes, I think we can help.
Also, did you use ‘iptables’ or ‘firewall-cmd’? And which version of CentOS are you on, I don’t recall where it changed. I built myself a CentOS 6.0 machine yesterday to look at this but I’m afraid I got interrupted.
We have default content in the BES Support site to add an exception for BESClient to the iptables firewall for RHEL, I’m pretty sure I can adapt that to CentOS.