For whatever reason, watermarks are sometimes necessary, even on drawings. Here is the simple method to add a watermark to your drawing:
1.Open the drawing.
2.Edit Sheet Format.
3.Use Annotation Note to create and place the text that will become the watermark.
4.Edit the properties of the Note to adjust its font, angle, size, etc as desired.
5.Highlight the Note and change its color using the Line Color function. For best results, assign a very light color to the Note.
6.Right Mouse Button click on the Note and select "Display note behind sheet".
7.Edit Drawing Sheet.
The text within that annotation note will always appear under your drawing elements. You can place a link within annotation note to a custom property to allow the user to change its content without having to edit the sheet format.
