In Easel the carve will only start at visual grid X0Y0.
You can not change the start position.
But you can make start point anywhere on your design.
You can move the design so X0Y0 is placed say top right of the design, vs bottom left that Easel assume.
Check this for an example:
Regarding zeroing there are two main methods, one is zero relative to the material and the other is relative to the wasteboard. I usually choose the latter because that give me a firm reference to my waste board. My waste board is also skimmed true so I know it is uniform in height relative to end mill height.
Say my material have a nominal thickness of 12mm, but may vary +/-0,5mm.
- I then jog my bit (or use a probe) down to the wasteboard and when it touches I know that is “Wasteboard Zero”
- Then I jog up (retract Z) 13mm. (If I want to cut through I then set cut depth = 13mm
- Move end bit to X/Y start position. Use this as “Confirm Home position” and you are good to go.