Thanks to have replied.
1 - The data are arranged like this :
For more details, you can take a look to the QV application I have attached to the post.
2 - You are right, Only() is enough.
3 - vBestSoftware is defined in the Variable Overview, and the expression I have written is :
I have done some tests, and this variable seems to return a String.
Hope it helps.
Sorry for late answer. If you change the variable to evaluate directly (add = in the beginning) and then do not use variable expansion on other places (eg change $(vBestSoftware) to vBestSoftware in text creation). You should though keep $(vBestSoftware) in the expression for Word Cloud as before.
This is due to that variables are not evaluated in expressions, so they need to be evaluated before (keeping one value throughout the evaluation of the expression over all dimensions).
Another way is only to change the expression to evaluate the varible directly: