Hi,
The latest version 2.6.3 does improve on the behavior of Step Time entry, but there are some remaining quirks to improve.
A couple of things that we've found that help:
1. Don't use the Zoom feature while using Step-time - it throws off the cursor advancement (and leaves "gaps" which will then be filled with a rest

)
2. Don't use the scroll wheel on the mouse during Step-time recording.
3. If a rest gets inserted that shouldn't be there, you can simply select the note to the right of the rest, and then press the Shift key on your keyboard along with the Left arrow button to shift the note back into its proper position.
Sorry for the remaining bother here.
ttfn,
Sherry