Is it possible to change the color of one word only in a multiple values check box field ?
I don't think so...but you could easily highlight one word by putting a colored rectangle behind it if that's what you desire.
You could split up the check box field into multiple items and have control of each one however you like.
Use booleans with values of 1 and blank...then hide the number...and enter what ever text you like as a text element to describe it.
If your checkbox value list is a "custom value list" of fixed entries, rather than dynamic (based on field contents), you could position a separately formatted text block over it, or over just part of it, and format the text within that text object any way you want.
You may be able to use a simple custom function and a calc field ( text result ) to be able to produce a result to position on top of the checkbox with your text color. You probably would want to use a monospaced font such as Courier New to get away from various leadings and text spacing.
Custom Function Name: colorValue ( thelist; text )
Let ( k = ValueCount ( thelist );
Case ( k > 0;
Case ( GetValue ( thelist; 1 ) = text; GetValue ( thelist ; 1 ) & ¶; " " & ¶ ) &
colorValue ( RightValues ( thelist ; k - 1 ); text )
Then in your calc you would call the function
colorValue ( ValueListItems ( Get ( FileName ) ; "YourValueListName" ) ; "theText" )
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