I totally misinterpreted the "F-keys" matter here.
This was due to my own personal dream: using my MacBook "fn" key as a modifier (other than Cmd, Alt, Shift and Ctrl).
I know I can remap it to another modifier (at least I know i can turn "fn" into "Ctrl" key with DoubleCommand)... but this is just not what I'm seeking.
Is there a way to build shortcuts to the likes of, say, "Fn+5"?
I'd kill for that (or shell some bucks, more realistically).
And yeah... I'm pinned to the free, excellent Spark when it comes to keyboard shortcut managers.