I am almost done with a definition to create columns out of EXCEL files
for there is the TOP level Parameter I not yet succeed to set it.
I check this discussion, referring to Builtin Parameter but
the node to Set Builtin from Archilab package throw an error.
It is the first time I tried to set a Builtin Parameter, the error comes from.
I feed columns, just created from another node and
level names, as string. But that not seems the error that pops up.
List [objects] has not attribute get_Parameter…it says.
Sorry, Do you want to set Top to constraint for the column?
yes that was it. I do not know why there are 2 replies of mine though! 
thanks.