Thank you very much for your reply. Yes, you are correct about the separate Eclipse installations.
Using the -data instruction with my Flex Builder installation caused a failure to start with a "Cannot start JVM" message. I hadn't thoroughly explored the Window menu in my addled state of mind last Friday afternoon, however, and closing all perspectives and reopening Flex Builder did work.
Meanwhile, adding the -data instruction to the Tersus shortcut does eliminate the error message I was getting there.
So I'm back in business :-)
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