Hello david555
Probably your problem is related to SELinux. To check this you can:
1) temporally set permission mode
sudo setenforce 0
2) run NoMachine:
sudo /etc/NX/nxserver --restart
3) try to reproduce the problem,
4) set SELinux’s enforce mode:
sudo setenforce 1
if you aren’t able to reproduce the problem, then we check deeper
SELinux logs.
Anyway a standard set of logs will be helpful. Gather them like is
described in:
https://www.nomachine.com/DT10O00163#1.1
and send to forum[at]nomachine[dot]com.