Magic_fubu is correct. Your formula would have worked, by the way, except you've got the "buy-ins" variable wrong. First, no variable has a dash "-" in its name. This would confuse the parser and make it think you're trying to subtract one variable from another ("buy" minus "ins"). Second, in the case of the Overall Formula, "count(scores)" is basically the same as "number of buy-ins". So your formula would have been:
assign("c", count(scores))
if(c = 10, sum(top(c-2, scores))), if(c = 9, sum(top(c-1, scores))), sum(scores)
or, since you know what the value of "c" is in your "if" statements:
assign("c", count(scores))
if(c = 10, sum(top(8, scores))), if(c = 9, sum(top(8, scores))), sum(scores)
Which, of course, simplifies to:
sum(top(8, scores))