Axis - how to tell which line of g-code is executing? It is not highlighted.

The LinuxCNC 2.1.14 Axis documentation says:
“When the program is running, the line currently being executed is highlighted in red.”
I am running 2.7.14 recently downloaded from the Linuxcnc.org site and it does not highlight the line currently being executed in red.
How can I find out which line is being executed?
Also, the documentation says:
“4.1.3.4 Text Display Area
By left-clicking a line of the program, the line will be highlighted in both the graphical and text displays.”
It does not do this either. Can someone tell me how to enable this?
I have searched the Linuxcnc forums and read the v2.7.14 docs to no avail.
This is a new install and I am a new user so probably user error, but I cannot debug the g-code if I cannot see which line is failing.
The only 'customising' I have done is to set home search and home latch velocities in the .ini file.

HI
you can
RIGHT klick on the G-code and say Run from HERE
GOOD advice to start at a Z up line

Thanks andypugh. Your comment helped, and I've now learnt a little more about g code with enabled me to debug it.
I am running the first set of g code that I've generated from Fusion 360. As you said, Axis does not highlight the 'set up' commands at the beginning of the g code. This is what was confusing me. However it also doesn't seem to highlight the first line of motion code that it executes if that line fails. The first line was a G53 (edit to correct code) command that was driving the Z axis into the limit switch. I edited the command (to Z-0.2) and it is working now. I now need to figure out what I did wrong in Fusion 360 to make it trip the limit switch. Thanks all for your help. (so much to learn - sigh!)