Thanks, but it does not answer my question.
First of all I am talking about the title block, that is attached to the drawing when you place it on a printing sheet. I know that as for simple text you can change all the options easily.
For the title block, the solution given before
this changes the background colour (the rectangular box underneath the text object) to black, so you cant really use it for any other background than black, as the black box stays there.
Have a look at the attached jpg. The 'title' is set to "background=opaque", so it changes to black... the 'scale' settings are: color=white, background=transparent and as we see it's still black.
As i cannot find the setting for changing the lines colour within the title block family(you can't get an access to lines settings) the circle around the sheet number '1' stays black... The white dividing line's colour is set in 'properties' dialog within the project itself, so it's visible.
It looks to me that it's either myself still learning, or Revit is 'cool' as long as you use the main features provided, not trying to customize them any other way (which is supposed to be so easy and fast).
any other hints?
L