Hello!
Is this error occurring on the title scene?
The only scene customized by this plugin is the title, which actually does not customize how the windows are created, it just repleaces the static background image with a map with moving events.
Although it is not the case with this one, there are other plugins from my library that do not use the window layer aggregator on scene objects, which may not be compatible with SuperTools due to that.
However, the "$dataWindows" object from the code snippet you shared is not an engine default object. I'm assuming it is created either by the SuperTools plugin, so the issue would need to be tackled on SuperTools, and not in TAA_MapTitleScreen (which at least is not even shown in the stack trace error).
I hope this is of some help.