My cygwin installation can display simple X11 clients such as xterm. A 
complex client such as git-cola, launched from a remote RedHat Linux 
machine, will cause all X11 windows under cygwin to become unresponsive. 
Windows Task Manager says "not responding."

This problem occurs with recent releases of Cygwin/X11. The attached 
cygcheck.out indicates the last X11 version that works well: 1.18-4.1. 
All other cygwin packages are up to date.

I realize that this is a sub-optimal cygcheck.out to send. Please 
describe what I should do to begin the debugging process. I would like 
to have a plan before I switch to a Cygwin configuration that gives me 
problems.