Zexplore is simply lacking awareness of ZAPI 1.32. You can safely use version 1.31 for the vast majority of operations...you might encounter an occasional issue if there is a discrepancy between 1.31 and 1.32, where Zexplore is using the 1.31 specification but 1.32 differs in some way.
If you're looking at the ZAPI docs, and not relying on Zexplore 100%, you'll be able to spot the differences. There is also a "What's New" section of the ZAPI docs which should point out differences between the versions.
You could also use the internal Zoom tool.
If this post resolved your issue, please help others by selecting ACCEPT AS SOLUTION or adding a KUDO.
Thanks Andrew. That answer makes sense but my real problem was I thought ZExplore was refusing to connect to the cluster. It was just warning me about the API version difference. The GUI gave no visual clue that it also went ahead and accepted the conneciton and ran the workflow step(s) ... until I happened to notice it the next time I was trying it out days later.. Oh well, never mind.