How do you want to "sum" this "multiple" question?
Generally: In "multiple" questions you have to take in account the subquestions.
Do you want to know how may subquestions were selected?
Function count().
Do you want to calculate something depending on the combination of selections?
This was answered in your other thread about this.
Do you want to calculate a score based on all subquestions but with different weighting?
As you see in the "logic" part of your question there is only one assessment value in "multiple" questions; so you have to do this by yourself.
Let's assume you weight:
Subquestion SQ001 with 2
Subquestion SQ002 with 3
Subquestion SQ003 with 0.5
Subquestion SQ004 with 3
...
Either the "usual way"
{sum(if(Q1_SQ001=="Y",2,0),if(Q1_SQ002=="Y",3,0),if(Q1_SQ003=="Y",0.5,0),if(Q1_SQ004=="Y",3,0),...)}
or
with function "countif" (advantage; you can shorten, if there are identical values
{sum(2*countif("Y",Q1_SQ001),3*countif("Y",Q1_SQ002,Q1_SQ004),0.5*countif("Y",Q1_SQ003),...)}
or
knowing that the value of TRUE is "1" (therefore you often see in conditions the default value "1")
{sum(intval(Q1_SQ001 == "Y") * 2,intval(Q1_SQ002 == "Y") * 3,,intval(Q1_SQ003 == "Y") * 0.5,intval(Q1_SQ004 == "Y") * 3,...)}
If you use an suitable coding of the subquestions you may shorten using the "that" variable".
You do not see the property ".value". As said at the beginning, in "multiple" questions there are no individual assessment values.
So explain, what and how you want to "sum" this question.
By the way: In all aggregation functions you should use ".NAOK"
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