Yes it is milliseconds. Note that the sleep 100 command worked. The dwell command did not work regardless of how long I made the dwell time. If I inserted a break in the code and stopped between the mode changes and the move, everything worked fine as well.
If the dwell code did not work for this example, I doubt it is really doing anything when inserted between a DRO change and an axis move. The macros that I have seen that use the dwell coomand have a comment that says "pause for the DRO to update." I am wondering if the dwell is even needed or if I shoul be using sleep instead of dwell for those instances as well.