Something I discovered is that it's possible to have multi-line text when setting the text via code. For example:
myGraph.SetInputString("Text", "Line 1\nLine 2");
So, this is sort of a workaround for those willing to use the API.
Oddly, the following results in an unknown character in the output: $"Line 1{Environment.NewLine}Line 2"
It seems Environment.NewLine isn't handled correctly by the plugin.