Composing with Sketches

I made a 4 bar phrase with a piano and Cello in Cmajor
I recorded the two instruments live with thekeyboard on feeling with the interaction of the 2 instruments

Now i do want make a sketch from the packed ( or rootcontainer ? ) { I like to see in the arrangement that i am in de sketch mode .. (playback: working Sketch: arrangementname ..gives this information )}

But now comes my point : i like to listen to all kind of chordchances and keys for this 4 bar phrase, but when i push a chord on the pallette for the live playing of the 4 bar phrase .. I cannot see where i must (want) play-in the chord in the 4 bar phrase ?
Is there a visual sign in the 4 bar sketch to see when i know on what measure i can play-in from the live pallette a chord ?  
Or other stated..with the live chord pallette where is the songpointer to see in a loop ( can it be looped the 4 bar phrase ?),  when i can chance a chord with live chord pallette.
Do i miss something ? .. i can't see how to do this ..has someone a idea about this ?
It is for Synfire Express.
Thanks

Note: i try to figure this out how it exactly works with making a sketch in Synfire Express: i did it in the container menu and someone might aspect that selecting with the launcher window and button Sketch he get the number of tracks what are also to see in the arrangement window ?
Must every track in the Sketch have his own container in the arrangement window ?

Wel the functionality what i do have in mind ..can't get yet in Synfire Express 

Ok i start with a sketch and a new sketch window opens i can add there some tracks with a mixer strip..than convert this to a arrangement and than this arrangement covert it to a sketch in the arrangement window ! --> now to control the harmony with a live palette, but i cannot punch in  the chord progression for a particulair chord.. when i choose a chord in the pallette probably it start  a measure 1 over and over again  

In other composer program there is a punch in possible for a loop ..so suppose say you are satisfied with measure 1 ..set the punch in  measure one  and the loop start in measure 2 ..this is repeating and the punch in comes in at measure 1 and the loop for measure 2 ..so you can  try out some chords( you need for that a running songpointer ) 
Looping and adding new symbols to build up a theme..