speech color in custom text window GUIs

[wynni2]

Using Sierra-style speech with an opaque background, I noticed a little quirk: If I use the default text window GUI, the characters' speech is printed to the GUI in their speech color.  If I use a custom text window GUI, their speech is printed in that GUI's "text color."  Is there a way to print speech to a custom text window GUI using a character's speech color (the way it does with the default window)?

Reading the forums I'm pretty sure the answer is "no," but I'm being cautiously optimistic. 

[dayowlron]

I may be wrong, but I thought a custom text window GUI is used for the Display command, not the Say commands, and the Say commands is a characters speech. The Display is used to show other messages that are not speech related.