Hi Dominic,
Unfortunately I do not currently have a subscription and not all of the thread you link to is available to read without one. In the one comment I can see, you said "You need to Running the Indexer After you have reviewed the search Plugins".
I assume you are implying there is a finder plugin that indexes the T4 Page builder content but I can not find one installed as part of the T4 Page Builder install. I have attached a screenshot of my installed finder plugins.
If there is a finder plugin available for the T4 Page builder could you please provide a link to a location I can download it?
The other part of you comment was about running the Smart Search indexer and I already do that on a regular basis to include PDF file indexing via another 3rd party finder plugin.