A script may have multiple <expt>s. Hence, as always, you are required to specify an element's name when you are trying to reference an element's property. If you have not explicitly named the one or several <expt> elements in your script, they are given numerical identifiers internally as in
/ blocks = [1-6 = myblock]
/ postinstructions = (Break)
/ trials = [1=mytrial]
<%if (expt.1.currentblocknumber < 6) item.breaktext.item(1) else item.breaktext.item(2)%>
/ 1 = "You have now completed block <%expt.1.currentblocknumber%> out of 6.
Please feel free to take a short break now. Before you continue, we remind you that the words on the sides of the screen may have changed."
/ 2 = "Thank you!"
/ stimulusframes = [1=mytext]
/ validresponse = (57)
/ items = ("Press SPACE")