Dont have much time to read fully but have looked through quickly and responded to some.
Starts up at -2.550, -3.442 instead of 0,0
I presume you are meaning X and Y coords here? If so then it depends what you have set up, if you choose to have DROs persistent then it will show what you had when you shut down. There are other optyions and can be found from Config menu then General Config page.
G80 seems to be ignored.
Please give an example
Disabling X, Y, Z, A, B, C on settings screen only partly disables them. The motion is reduced to 1/10th. Under certain conditions.
Not sure what you mean by this, can you be more specific in how you are disabling the axis? And what are the certain conditions?
G97 is not documented anywhere, yet it shows up at the screen top.
G97 is mainly a Turn feature, it sets the S word to RPM rather than G96 which is surface speed, it is mentioned in the turn manual.
Loading a file resets much less than it should. Keep the machine coordinates, but everything else should go to defaults.
Your G Code should contain all of the options you want rather than relying on Mach doing it as Mach doesnt know what YOU want as a default. Again General Config has options for this.
Mach3Mill burns 50% of CPU cycles before the program file is even loaded. Ideally, when the program is not running, CPU usage should be near zero.
This is a development meant really for testing of the screenset that will be used in Rev4 of Mach. CPU here is about 7% when idle. What specs computer are you using?
It would be nice if the Open File window would find .ngc (EMC and KMotionCNC) and .nc files in addition to .tap files.
It does if you use the drop down box
Metric/English unit confusion:
G20/G21 changes the active display -so the operator can't be sure what they are seeing. No indication -other than tiny g20/21- whether units are English or metric.
Again an option whether to keep native units or change to chosen.
Jog doesn't work right. Sometimes it just goes dead and is unresponsive, the a minute later starts working again. In metric mode, the units are all botched.
Sounds like your computer is either borderline of is getting bogged down with something running in the background.
Substantial rounding error:
x1 goes to 0.9906
x.012 goes to 0.0
x.013 goes to 0.0254
If internal state gets set wrong, even G20 will not fix this.
Dont have a clue what you are on about here, no rounding errors for me and if its just the display showing that then likely it is your resolution that is course, ie your steps per unit.
Tab key: MPG is not pulled out as far as it should be (right half cut off). Sure, it can be repositioned, but why not get it right the first time?
As you have discovered you can reposition and once set to where YOU want it it will stay that way.
Load scorpion.tap file. Repeatedly click "Regen. Toolpath" button. Sometimes the image disappears completely. Doing "Cycle Start" runs, but the image doesn't reappear. The Tool Path screen shows the program limits are all +/-9999.0000
Hold left mouse button in toolpath window. As image is tilted, it partially disappears. [Seems to be an issue just on my computer -video driver?]
Llikely to be your graphics and computers specs.
The roadrunner.tap file seems slightly corrupt -there are spaces and nulls at the end of the file and there is no ending M30 code.
You are not licenced so the Demo restrictions apply, one of which is 500 lines of code in Mill.
The Cross.tap file has a strangely sunken eye orbit.
Not sure what you mean here.
Typos on G-code tables:
Length is misspelled as "lenght" several places. (i.e. H Tool lenght)
Non-uniform capitalization (i.e. N line number)
What list is this?
Known issue: Entering values in dialog boxes are not saved unless the enter key is explicitly pressed.
That is intended
Focus is not given even when the G-code window is scrolled.
Focus of what?
No way to see what the internal "set next line" is set to.
You enter the line you want to go to in the DRO for Set Next Line. However in Demo mode it does not work.
Clicking "Zero X" when in "Machine Coords" zeros X without any indication.
What do you expect to happen? It is zeroing the DRO and you are pressing the button so you should know what will happen.
Input box not greyed out when in reset mode.
Input box?
Cannot scroll code window when Single BLK is active.
Fail to see the problem with this. You are in single block so why scroll the window?
Clicking Reset turns off Single BLK mode.
as above but again there are options on General Config page, not sure if that is one or not.
ESC does not toggle Reset, like the documentation states.
Documents are old, Mach is coded by one person who concentrates on coding as much as possible. You can however set up any hot key you wish to operate Reset, this is done via a screen editor.
Ok have to go now but that will maybe answer some of your questions and throw up a few more
Hood