I guess someone will start accuse me in self advertisement... publishing the same links to my site more then once per day
From what I know, there is no way to modify what is recorded into MIDI clip inside Sonar. So whatever is coming on MIDI input is recorded verbatim (the same as with audio). But it is possible to process it on the fly by MIDI FX. Live: Input -> Track (recording) -> MFX -> Output and on Play Track -> MFX ->Output, so from VSTi/hardware synth on output perspective the result is the same as modification during recording. But in PRV you still see "original" MIDI, there is no way to change that.
If you want to "fix" the effect, for example to tweak the result in PRV, you should "bounce" the clip first. There are 3(!) ways to do this, depending on situation:
1) if you apply MFX to clip instead of track, bouncing the clip will apply the effect
2) if you have MFX in the track, you can "Process/Apply effect...", Sonar will ask you either you want to remove the effect after bouncing (to avoid doubling the effect)
3) you can "Process..." clips by effect of choice, note that even in case you already have it in the track, absolutely new effect instance will be used for such processing, so you need to set required effect parameters again (you can save settings into Preset in the track instance and select the preset in processing to speedup that)
And now the links:
* with this one you just draw the curve, default (no changes) is linear, for example 50->50. For what you describe, you need another slope, for example 0->0 and 50->30. How it should look like for other regions is up to you:
http://www.azslow.com/index.php/topic,275.0.html * if still not exactly what you want and you know how to sum two columns in Excel (or have better programming experience...), you can write the algorithm yourself (without leaving Sonar):
http://www.azslow.com/index.php/topic,286.0.html