Hello D.Rose92

In My WinCC V8.0 Upd5 it works. If I change the ID 34 in Text library also the lable of the textblock changes (I do also not have to open the Graphics Designer again, it work instantly with reopening the config dialog)

If you uncheck the "Apply Project settings" you can also select another Text ID with a customized Text ID for example, also this works properly in my case

so check if you have installed the latest Update, perhaps this could be a difference

Bye Murof