In Single Strand, I could get a chase like you describe IF I checked the "Group All Arches" box and played with the Chase Size slider. I tried it a few different models and sometimes it worked well, other times a little goofy until I tweaked it in.
SingleStrand,None,Average,ID_CHECKBOX_LayerMorph=0,ID_SLIDER_SparkleFrequency=96,ID_SLIDER_Brightness=130,ID_SLIDER_Contrast=0,ID_SLIDER_EffectLayerMix=0,E1_SLIDER_Speed=8,E1_TEXTCTRL_Fadein=0.5,E1_TEXTCTRL_Fadeout=0.8,E1_CHECKBOX_FitToTime=0,E1_CHECKBOX_OverlayBkg=0,E1_CHOICE_SingleStrand_Colors=Palette,E1_SLIDER_Number_Chases=1,E1_SLIDER_Color_Mix1=2,E1_SLIDER_Chase_Spacing1=1,E1_CHOICE_Chase_Type1=Right-Left,E1_CHECKBOX_Chase_3dFade1=0,E1_CHECKBOX_Chase_Group_All=1,E1_BUTTON_Palette1=#00D900,E1_CHECKBOX_Palette1=1,E1_BUTTON_Palette2=#00FF00,E1_CHECKBOX_Palette2=0,E1_BUTTON_Palette3=#0000FF,E1_CHECKBOX_Palette3=0,E1_BUTTON_Palette4=#FFFF00,E1_CHECKBOX_Palette4=0,E1_BUTTON_Palette5=#FFFFFF,E1_CHECKBOX_Palette5=0,E1_BUTTON_Palette6=#000000,E1_CHECKBOX_Palette6=0,E2_SLIDER_Speed=1,E2_TEXTCTRL_Fadein=0.00,E2_TEXTCTRL_Fadeout=0.00,E2_CHECKBOX_FitToTime=0,E2_CHECKBOX_OverlayBkg=0,E2_BUTTON_Palette1=#FF0000,E2_CHECKBOX_Palette1=1,E2_BUTTON_Palette2=#00FF00,E2_CHECKBOX_Palette2=0,E2_BUTTON_Palette3=#0000FF,E2_CHECKBOX_Palette3=0,E2_BUTTON_Palette4=#FFFF00,E2_CHECKBOX_Palette4=0,E2_BUTTON_Palette5=#FFFFFF,E2_CHECKBOX_Palette5=1,E2_BUTTON_Palette6=#000000,E2_CHECKBOX_Palette6=1If you copy/paste the above XML into a cell of your timeline, you should see a green pixel chasing
But if you're looking for something like this:
http://youtu.be/ZHr0x68R58cI did it in LOR S3 and imported into xLights.