If they work in Camtasia 9 but they won't work in Camtasia 2018.
I would have to say 2018 is missing something. Are you running the newest version? 2018.0.4?
If you are, I would place an inquire with support about it.
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In the meantime, unless theres some feature you must use from Camtasia 2018.
I would edit your project in Cam 9. There's really not much difference between the 2 programs.