No, The Grbl updater will update your machine to Grbl 1.1 (which is required by CM4).
The problem here is a disagreement in how arcs are calculated / verified. AIUI, the possibilities are:
- Autodesk Fusion 360 calculates them wrong (Grbl is supposed to be very forgiving) — workarounds include: re-calculating in metric, turning off ramping in, disabling the use of arcs
- a post-processor influences Fusion 360 to get them wrong (we need to identify which one it is)
- Carbide Motion in re-writing the arc information complains about unnecessary data being left out as it is streaming — this seems to vary by version / build
- Grbl wrongly assumes an arc is invalid when Autodesk Fusion 360 has calculated one correctly — this last seems pretty unlikely given that this problem has been on-going.
Please send problem files in to firstname.lastname@example.org w/ a note on which version(s) of CM they have problems with, and what settings were used in Fusion360 and esp. which post-processor was used.