CopyMaster 300 - Printing above bed, Marlin V2. (no replies)

Hello all.

Wonder if anyone could offer advice on config files please?

I've been working/struggling on updating the Marlin firmware to Bugfix-2.0.x for a while now on my (relatively unknown) CopyMaster 300 with an original BLTouch V3.1 probe, (I believe its a CR10 type clone)

I've got the probe working now, compiled & flashed the firmware fine (using VS Code, PlatformIO & the Auto build add in process) machine homes & moves fine though there is a delay in processing the next movement it feels like it pauses after homing each axis.

Everything goes fine levelling the bed & setting the Z Probe Offset, sending G1 F60 Z0 the machine places the nozzle where it should be, all is well in Simplify3D's Bed Levelling wizard too.

Hit print on a freshly sliced xyz calibration cube & it attempts to print a few mm above the bed like its ignoring the Offset (via both SD card & direct USB print).

I have the current config files (looks like Marlin 1 RC7) and matched up everything & if i flash back to the original firmware the same cube prints fine.

I'm definitely missing something however it all looks ok to me.If anyone could offer suggestions on what I've missed i would be grateful.

Attaching both New & Original files.

Edit to add start Gcode

G28 ; home all axes
G29 ;ABL SEQUENCE
G1 Z5 F3000 ; lift
G1 X20 Y28 F1500 ; avoid binder clips
G1 Z0.2 F3000 ; get ready to prime
G92 E0 ; reset extrusion distance
G1 X120 E10 F600 ; prime nozzle
G1 X150 F5000 ; quick wipe

Thanks in advance
James