Select multiple lines by pressing Shift while clicking on a line.
Dissolve start controls at what time in the morph the points near the selected lines should start changing color. Before it starts changing color only the color values of the first image are used.
Dissolve stop controls at what time in the morph the points near the selected lines should finish changing color. After it has finished changing colors only the colors of the last image are used.
Start point begin move controls at what time in the first point (drawn as a filled rectangle) starts moving.
Start point stop move controls at what time in the first point (drawn as a filled rectangle) stops moving.
End point begin move controls at what time in the last point (drawn as a framed rectangle) starts moving.
End point stop move controls at what time in the last point (drawn as a framed rectangle) stops moving.
If the lines are connected, then the points between the first and the last control point will have values inbetweened.