Hi @MattEl5
I haven't tried this but I doubt this will work:
The style configuration operates on the object of the row - in your case, the PROJ.
What you're doing in that cell is iterating over the project tasks (very low performing at scale) and printing out one specific task.
That task's properties have nothing to do with the project - so you can't color in the cell if "one result of the iteration has a date that is...".
your options:
1. do a task report.
2. use Fusion/API to set a hidden field at the project for the "Strategic Planning Meeting" plannedStartDate - then you can colorize the cell based on this value.