To change the Zero on an axis during run - like Z for example...Do a 'feed hold', then if you need to move Z zero up .010 - add the .010 to the DRO reading, zero Z, take Z up to the reading + .010 and zero again, then back down to the reading without adding the .010 - that is Z up .010 from where it was. Then cycle start to end the feed hold. You can do any axis this way during a run.