Cakewalk's Master Drum Class - Step Sequencer Method - Advice Please

Hey ya'll.  It's been awhile since I've accessed these forums, but I find myself with some time for recording again.  Found and received much good info here in the past - back for more - thanks in advance.
 
I struggle with creating/arranging drums for my songs.  Just wondering, from within Sonar, what some of you folks do.
 
I'd like to use the SD3 or SI samples included with Sonar, but it's hard to get a two-measure pattern from a four-bar sample.  If I modify a sample clip by splitting or shortening or lengthening and then sliding it around to say, put the sample's drum roll right where I need it, there tends to be a stutter or a gap between the unmodified clips and the altered ones.  I wasn't using Take Lanes (Layers) for the individual clips though, maybe that's a problem?
 
I guess I could copy the samples to new Take Lanes and modify them in Step Sequencer...?
 
(I did watch Chuck's video using SD3 and the PRV - I like the Step Sequencer interface.)

Ok, thanks Scook.  As a newb I'm a little, make that a-lotta, shaky on MIDI, but I'll try to remember that.
 
I tried alternating the MIDI patterns between two separate Take Lanes, such that a cropped clip was not adjacent to another clip, if that makes any sense, and that eliminated the stuttering.  I froze and thawed the synth and good to go.