If you create a bar plot froma given dataset you can format the
columns by right clicking and choosing the desired options. In the tab
that opens there is a slider which is supposed tho set the level of
transparency of the column (selceted area). But so far i couldn't find
a way how to use this slider.

I know that there is an alternative way to get transparent bars by
creating a rectangular object formating it and the use copy - paste.
But i wonder what is the slider for if you can't use it?

Does anybody know have an idea?

Cheers,
Thomas