Below is a link to a tutorial about inserting and using corner windows. The windows can be adjusted at any time of your process as they are parametric.https://www.youtube.com/watch?v=JOrwOeZpCpE
In regards to the corner column. This is easy to do, just draw your corner column to the sizes you would like and then use the BIM Tool
. By using the
it will allow you to estimate the corner column.
I have attached an image of an example below.