Looking up a sum of data in several columns for specific values of another column

I have the formula:

=(SUMIF($J:$J, "Player1",$K:$K)+SUMIF($L:$L,"Player1",$M:$M)+SUMIF($N:$N,"Player1",$O:$O))-SUM($I:$I)

This looks up if Player 1 was in the top 3 scoring zones and adds up the players total score.

I have another column in this table of data labelled 'Number of Players'. I was wondering how to lookup the total score for this player in the games he played under 6 players for example and the games he played in where there were other six players.

I've tried using that formula ^^ with variations of IF and SUMIF formulas to try and figure it out, but I keep getting formula errors or it just returns with the total score, and not just with the total score under 6 players.

I am also trying to create a graph of date on the x axis against score to date on the y axis - everytime I try, the x axis is always numbers instead of the date? :S

Any help?

Cheers
Matt