DIV and VALUE error on ROUND AVERAGE and IF ABS statement

I'm having a couple issues with formulas which i'm not smart enough to solve, I hope someone will be able to help me

Explanation:
K to N is filled manually
O is the average of K and M with round 0, formula =IF(COUNTA(K4;M4)=2;ROUND(AVERAGE(K4;M4);0);"")
P is the average of L and N with round 1 decimal, add /10 to the end, formula =ROUND(AVERAGE(L4;N4);1)&"/10"
Q is the difference between K and M with ABS, IF=0 leave blank, formula IF(ABS([K]-[M])=0;"";ABS([K]-[M]))
R is the difference between L and N with ABS, IF=0 leave blank, formula IF(ABS([L]-[N])=0;"";ABS([L]-[N]))

EDIT: Sorry for the weird Q and R statements, the K means coloumn K and so on.

Screenshot 2022-01-14 at 18.16.49.png

The following errors occours:
P displays error DIV/0 if L and N is blank, P should remain blank in this case
Q displays error VALUE if K or M is N/A, Q should remain blank in this case
R displays error VALUE if L or N is N/A, R should remain blank in this case

Hope everyone has a great weekend!

Brrrr. Too many words and a picture.


A picture is worth 1,000 words. An Excel sheet is worth 1,000 non-editable pictures.

Please read the yellow banner about sample worksheets, at the top of the screen. Act on its guidelines and post a SMALL sample sheet complete with an explanation and some expected results.

Should be attached now Glenn