Strobe Motion in VS9

[JARROD1]

I am trying out one of the new video effect in VS9 called 'Strobe motion". What happens is, I drag my video clip into the time line and place the strobe motion effect on the clip. Kepp in mind that the clip in the timeline is a trimmed clip because I do not need the other footage in the original, just the stuff I trimmed. When I place the strobe motion on the clip in the time line, the effect somehow flashes between what I have trimmed and the total clip in the library. Is there anyway around this other than rendering just the exact footage I need?