Rob, I think the prob­lem here is that you don't know how to use KSPread.

Here's the cor­rect syn­tax for your ex­am­ples (untest­d, but should work):

=F7 * ( 1 + MAX( 0.20 ; (F7-F2)/F2/5 ) )

=MAX(A1;100)

In fac­t, the one that you men­tion as work­ing, MAX (A1:A2) works by co­in­ci­dence (Un­less you re­al­ly want the max over a range, in­stead of the max over two cell­s).

Can we get that not-­grumpy week any­way?