Using the Advanced Midi Editor
The advanced midi editor has been enhanced in version 4 of the Polyphonic Wizard and gives you more control over the trimming and channel selection process, whilst retaining ease of use for users with no musical knowledge.
You can access the advanced midi editor by clicking on the 'Advanced' button on the Polyphonic Wizard standard trim screen.
When you click on the button you will be shown a window similar to this:

To use the advanced midi editor:
Exit without Changes
Pressing this button will take you back to the standard midi trim screen.
Start Preview
Pressing the 'Start Preview' button will start a playback of the current midi file. You can click the include and remove tags on each channel to turn the channels on and off while the midi is playing.
Pressing the button again will stop the preview
Apply Changes
The 'Apply Changes' button will apply the changes you have selected and move you forward to the next stage of the Polyphonic Wizard - select a phone.
Include / Remove
To the right of each channel you will see the text include or remove. Simply click this text to include, or remove a channel. When a channel is included a small green icon will be displayed to the right. When a channel is removed a small red icon (x) will be displayed to the right.
Instrument Name
Each channel has an instrument associated with it. This is shown on the left of the screen.
Clicking on the arrow to the right of the instrument name will move the trim / start bar to the first note on that channel, this is very useful to perform exact trims where you want to start when a specific instrument starts playing.
Clicking the loudspeaker to the right of the screen will move the trim bar to the first note on that channel, and start playback of just that channel, so you can hear the instrument on its own.
Trim Bars
At the top of the window you will see two arrows, with lines running down from these arrows. These are the trim bars.
Simply click on the arrows or bars and drag them to where you would like to start playback.
If a midi is playing back when you drag the trim bars, playback will be automatically canceled.