1-In the main Track View of Sonar (the default view) go to Views and select Event List.
2-In Piano Roll, you can change duration by selecting the Smart Tool (the one that looks like a star) and putting your mouse over the end of the note. You can then drag it to make it longer or shorter. (You can also quantize afterwards if you think you didn't drag it exactly right.)
3-SUGGESTION: This is slow, but in Staff view or Piano Roll view, you can right click a note, and then change it up or down a few steps to see if there is another note behind it. For example, if the note is C3, click the spinner to move it up or down to reveal a note behind it. Then you can delete one, move one back where it goes, etc.
This isn't what you asked, but I would 86 the drummer and just program Session Drummer 3. If you are a good MIDI drum programmer, you can create the part in a 1/10 of the time it would take to fix the mess you've got. If you're not a good drum programmer, get some MIDI loops. I've been there and feel your pain.
In my opinion, simple drum parts are always in good taste. Complex ones can be cool if you know what you're doing, but, when in doubt, keep it basic.
post edited by konradh - 2011/07/01 19:21:51