If he has steel lintels more than likely there's a 20mm gap or so between the plasterboard and lintel so more than enough room to fix in plasterboard fixingsAnd for added excitement you might have a steel lintel over the window. That’ll be fun drilling though (won’t be that bad just something to bare in mind).
Yes same here in terms of fitting. I had to move the ones which were left here away from the window a bit for that reason. Also it allows a bit of ventilation around them.My blind brackets are generally drilled in left/right in the reveal/alcove rather than to the top.
Need to remember to allow room for the window handles on the drop through, so don't mount directly next to the window. Give a bit of a gap so that the blind can naturally be lowered without the handle being in the way.
Why would you use a batten on the lintel.. Just screw the brackets directly to the lintel using self tappers.