I need 6/8 time in section 1 but then it changes to 4/4 time section 2. How do I change it?
There are buttons for changing the time signature of the current selection in the Chart menu of the editor:
However, as you may have discovered, they cannot be used to switch between 6/8 time and 4/4 time. This could potentially be an option in the future, but it’s a more complicated scenario to implement so I left it as unsupported for the first release of the mid-song time-signature changes features (which was added just this last summer).
For now, the only way to switch between 6/8 and 4/4 time is to use a medley.