I am having an issue with the VBO exports. I did four sessions during testing last week. I have exported the data in the vbo format and loaded it into CT ok. The first three sessions are fine. The last one has some very strange lap times (much longer).
Once you have exported a KML file for a multi-lap, or an incomplete lap, open it in Google Earth and watch the line driven and the position if the trigger. You will be able to see GPS accuracy, distance between line driven and trigger, etc.