PC MILL55 with WINNC incremental jog pc keyboard control

Hi all. I'm successfully using an Emco PC MILL55 with the original hardware (pc RS422 card) and winnc software V13.62 emulating a Fanuc O-M controller. I'm using the pc keyboard to control the machine but the original 'software description' book, edition H2001-8 I have, leaves a lot of detail to be desired. In particular, I'm stuck on the key sequence to enable incremental jog ; I've tried most possible combinations of cntl/shift/alt along with the 'top row' numbers 1 to 4 as indicated in the book but nothing seems to work. Is anyone able to help me in this area please ? I'm able to jog as expected in 'normal jog' mode and am able to alter feed rates, and therefore jog speed ok. I'm unable to get the Genius digitizer tablet and overlay working to see if the 'incremental jog' function works with that - but that's another story. Any help appreciated.
Peter

I've now solved my own problem with the MILL55 and WinNC / FANUC 0M using the PC keyboard for incremental jog....
1) Select jog mode, F1, F6. Jog mode is confirmed……
2) Press F1 to bring up the ‘F1 menu’. We’re still in JOG mode but notice the right chevron (>) to the right of the menu bar.
3) Select the right chevron (>) to the right of the menu bar with the mouse to display the incremental jog selections. I haven’t yet discovered how to select the chevron with the keyboard.
4) Select the desired increment. The mode changes from JOG to STEP
5) As far as I am able to determine, the jog increment is not displayed, however the incremental jog does now work using the standard jog keys on the number keypad.
6) It’s useful to be able to see the actual jogging process and actual position changes so…..Press F12 to bring up the position menu. Note, we’re still in STEP mode.
7) Select F3 to display position information.
The jog keys work in incremental mode as expected – this has been confirmed with a dial indicator placed against the bed.