Hi,
what I found was useful was to 'declutter' the toolpath. Mach as shipped has one colour for the background, another
colour for rapids, yet another for G1 moves and yet another for completed moves.
I found that the toolpath became so cluttered that I struggled to determine a good toolpath. I found with my PCB isolation
routing jobs that the best way is to make the rapids the same colour as the background, ie it disappears.
May I suggest that you 'disappear' one or two toolpath elements as see how much better you can veiw it.
To be honest if I really want to view a toolpath, say for verification before committing the job, I use a standalone Gcode
viewer. Mach4's toolpath display will never be a highly resolved and richly featured display like you would expect from a
dedicated viewer.
Craig