As an update: Ive just gotten the X Tilt / Z-Leadscrew setup working now, and I think this was 90% of my issue! Ive run 4 prints now using the x tilt correction before each print and Ive NOT needed to babystep in with PLA [ only filament tested so far ] .... Amazing! At most it may need .02 / .04 tweek to be PERF.
Thanks guys ... yeah I just punted and dl'd 3 main files [ as I dont use PanelDue ] and - installed ...
Guessed on the order... just did the main baords fw 1st then, wifiserver then DWC file.
Im using Matterhackers [ they are just down the street from me ] 1.75 Aqua PetG Pro
Installed DWC 3.1 w/ rrf3 - new duet wifi 2. Cartesian Prusa [ Zaribo ]
Trying to home axis - get errors [ G28 - Failed to Home ] - using sensorless homing.
Tried using G28 X0 / G28 Y0 - since the DWC dashboard options do not exist ...
Thank you for the great reply - im having similar issues and have been for ages. I had been chalking it up to the BuildTac Magbed stick on sheet as being the culprit - but I suspect now it is - for me - a combo of all those 3 issues you mentioned above + the Magbed.
I need a bridgeport Knee mill some MIC6 
the bed may bow .... however - your initial Mesh Grid probing had it nearly perfect at one point - not sure if that near perfect mesh grid probe routine early on was HOT or ambient - pretty sure you mentioned it was HOT.
Im going to go with a combo of all 3 of the items mentioned by DC42 - Heat causing the pcb to bow slightly .... some minor twist [ perhaps a very small amount ] and MOST of this imho is the 8mm rods sagging in the center of the X travel. Now you understand why I wanted linear rails or a 10-12mm smooth rod setup for X. Ive opted for my new printer - MGN12 - like Stefan Webers.
You resolved the shortcomings in the Y axis so well - now its exacerbated the flaws in the X
Just my humble thoughts ... the modding never ends
Thank you for the updates !
Ive been going bat isht crazy with baby stepping since day one with duet - in that I have to restart printer every print and re mesh bed level etc and resett baby stepping because there seems to be a "stacking" of the offset or some division of the gross sized offset between prints ... Can you elaborate a little on what was corrected / changed pertaining to the babystepping or link to the thread where it was discussed ?
Thanks again ...
Sputty
Nice !!!!
Im jealous I must say.
Well I never knew if you were a "decking Man" or ... DEC Kingman - mystery SOLVED !!! 
Looking forward to seeing / reading of your 3d exploits.
Enjoy
@dc42 said in Pause / Resume from DWC buttons - nasty head crash - but WHY?:
@sputnikoc3d said in Pause / Resume from DWC buttons - nasty head crash - but WHY?:
2.02RC5
You should not use beta or RC firmware versions once the corresponding stable release is available (2.02 in this case). As @resam said, there was a known bug in this area in some 2.02RC versions.
Thanks David ...
Lesson learned then. I wondered if I had changed something somewhere that may have caused it ... I had not had the printer up and working for over a month - and needed to get a friends parts printed ... asap. Didnt think to see if there was a new version before rockin and rollin. Lesson #2 learned
Im up on all the latest stable full releases now.
thanks to all for the assist.
and this is tested ... per filament type and for each nozzle diam ... correct ?
And that you deckingman ... and all
2.02RC5
wifi 1.21
web interface 1.22.5
I suspect the fact that I may have executed a few DWC commands from the windows - may have caused the board to lose track of its location ? I didnt think it would but perhaps it does. Trying to search for answers ...
Done this a few times in the past but it no workieeee this time.
Hit Pause ... Print head moves - sits idle with heat still on...
Hit Macro - for releasing the Extruder Motor [ M84 E0 ]
remove filament - cold pull style - manually ...
insert new filament feed - press in till a bit of oozing [ petg 245*C ]
tweez off ooze
Hit Extrude for 50mm on the DWC panels buttons for Machine Control Window
Hit Resume .... [ i remember it used to work ] .... but alas, in this case - hard crash into part.
Looks like it was trying to go to gcode's beginning and print a Purge Strip.
Clueless in Cali
; pause.g
; called when a print from SD card is paused
;
; generated by RepRapFirmware Configuration Tool on Wed Jan 31 2018 09:50:41 GMT-0800 (Pacific Standard Time)
M83 ; relative extruder moves
G1 E-4 F3600 ; retract 4mm of filament
G91 ; relative positioning
G1 Z5 F360 ; lift Z by 5mm
G90 ; absolute positioning
G1 X0 Y0 F6000 ; go to X=0 Y=0
=============================
; resume.g
; called before a print from SD card is resumed
;
; generated by RepRapFirmware Configuration Tool on Wed Jan 31 2018 09:50:41 GMT-0800 (Pacific Standard Time)
G1 R1 Z5 F6000 ; go to 5mm above position of the last print move
G1 R1 ; go back to the last print move
M83 ; relative extruder moves
G1 E4 F3600 ; extrude 10mm of filament to undo the retraction from Pause.g
@dc42 said in Tutorial - running Duet Wifi 2 in Access Point Mode ?:
M587, M588 and M589 commands do not work in config.g because the WiFi module isn't enabled until config.g has completed, and only then if there was an M552 command in config.g. So to execute these commands, go to the console using YAT, PanelDue or DWC (if you are connected) and then:
- if you are not connected via DWC, send M552 S0 to start the WiFi module in idle mode
- send the M587, M588 and/or M589 command(s) you need
TY DC42 - that about sums it up. USB or PanelDue of no M5882.
even if I had a paneldue [ and this is based on never having USED one ever before ... how would one MAKE a new macro on hte paneldue - to issue the commands to make a macro and send M587/M588/M589 .... guess there is a interface for typing characters on it ?
Off to the elecreinics store to find a long enough USB cable now that will reach from Intel NUC to Printer. Pronterface ok here for this YAT is just not my cup of tea - at all.