So i've worked on it a bit more and so far I developed lists so that:
<list g_startX>
/items =(parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2,parameters.h2)
/ selectionmode = list.problemnumber.currentindex
</list>
...
and so on for the rest of the fields (the h2 is temporary to just get it working first).
Then I modified the trial.newround such that:
values.b_targetY=list.b_targetY.nextvalue;
values.r_currentX=list.r_startX.nextvalue;
values.r_currentY=list.r_startY.nextvalue;
values.g_currentX=list.g_startX.nextvalue;
values.g_currentY=.list.g_startY.nextvalue;
values.b_currentX=list.b_startX.nextvalue;
values.b_currentY=list.b_startY.nextvalue;
picture.R.hposition = list.r_startX.nextvalue;
picture.R.vposition = list.r_startY.nextvalue;
picture.G.hposition = list.g_startX.nextvalue;
picture.G.vposition = list.g_startY.nextvalue;
picture.B.hposition = list.b_startX.nextvalue;
picture.B.vposition = list.b_startY.nextvalue
but I get the error: Expression '.list.g_startY.nextvalue' is invalid. Expression contains an unknown element or property name. What am I missing?