Hello,
Jumping into it, my workflow works fine when I have When an item is created as the trigger.

However (as needs have changed, we are now using a button flow) when I change the trigger to For a selected item, the workflow is now failing on the "Compose Sig1" variable - this is the same as above:
replace(triggerOutputs()?['body/SF15_SignedCus1'],'"','')

Do I need to change the formatting of the variable for this to work?