If I have to replace a broken router bit when using the X-Carve and Easel, is there a “resume” feature so I can exactly reposition the new bit and keep the settings?
You could restart the carve if you have, and used, a fixed reference point prior to setting your work zero.
Such reference point may be homing switches or a 3-edge finder.
The gcode could be edited as in delete the previous carved part of the code, but its not trivial.
Depending on the design one could also mask away in the design program those areas already done.
As @HaldorLonningdal says you could edit the G-Code but what I usually do is just to speed up the carve up to the point I reach the old position again.
Another option is to place white rectangles over the already carved pieces in Easel, to skip those.
For editing the G-Code I recommend using an online viewer, so you remove the middle part of the movements keeping the tool high while you reach the section you want to start the “Resume”. The only important part is just not to crash the bit into your work.