I know that the following is not a convenient solution, but anyway it's a possible work-around: 1. Assuming your (x,y,z) worksheet is already normalized, i.e. x+y+z=1 in data1, make a new worksheet (X2,Y2,L). L is for your labels.
2. Set the column values of X2 and Y2 such that:
X2=data1_a[i]+data1_b[i]*0.5
Y2=data1_b[i]*sqrt(3)*0.5
(Here, data1_a for x, data1_b for y.)
3. Create a scattergram of (X2,Y2,L), change the symbol size to 0, and set the X and Y axis ranges as 0 to 1.
4. Merge your ternary graph and the scattergram. Move the scattergram layer where you wish, and make the axes and tick labels invisible.
Hope this can be at least useful for you.
