Another thing you could try is to build your timeline into one effect, then COPY that effect to another effect.  Now build the sequence between the 2 registers (Learn SEQ - 1, 2, 1).  Turn on Auto Run & start the sequence.  

There isn't any way to do this unfortunately, however here is a workaround that might work for you.

Instead of building a timeline, Learn a number of single Emems instead. You probably want these Emems to transition from one to the next, not "cut", so Learn them as "Eff Diss" Emems. Still with me? Good! Now, Learn a Sequence of these Emems, and make the sequence end with the same Emem that it began with - so for example, make the sequence go as follows:

Emem 1; Emem 2; Emem 3; Emem 4; Emem 5; Emem 1

When you recall Emem 1, the switcher will automatically initiate the looping sequence of Emems. 

I have never had to do that.....

But what about inserting a "run" macro into the time line?