Attached a tex file and the generated PDF.

The first table is what I am trying to do. The second table is an example
about what I would like to accomplish.

I have two problems.

Because there will be a lot of tables I like to use a variable, so that
changes can be done in one place. That is why I would like to use:
    \getvariable{desc}{fieldHeading}
on the third line of the table. But then I get one column instead of five.
(The third is what I get, the fourth what I would like to get.)

In the first and last two rows I would like to have the field take the
complete row. Just like the example in the table under it where I use

Is this possible?

-- 
Cecil Westerhof