Plunge Feed driving me nuts

Hi can anyone help out Please.
I’m using the usual Mach 3,and latest LazyCam combo, but it seems that I cannot set a faster plunge feed. I know its me, and its probably something simple, but its driving me nuts.

I set up the tool in LazyCam including Feed rates, Rapid rates etc export to Mach 3 all ok except the plunge speed always reverts to F1 in the code. If I go and edit the Z axis code in Mach 3 to say F50 it works fine. So its something Im not doing properly. The Z axis is also ok in going from 0 (zero) to whatever +(plus) height such as rapid height but as soon as it gets back down to zero the plunge speed drops right back to F1 again.

Very new to this so I accept all criticism and any reference to being a plank. :)

Thanks Dave