I have the same problem.  x2go works, but it takes 2-3 minutes from starting the session until the remote session window appears.  Works fine otherwise.

This bug should probably be marked as critical, as it makes x2go barely useable for some use cases.  My me it's a bit annoying, but not that big of a deal.

I am running Gentoo Linux, x2go client 4.1.1.0, x2go server 4.0.1.22.