The watermark will also be exported by default at the bottom right of the red frame, unless you uncheck the checkbox 1. Electric circuit and connection points can also be exported with the checkboxes 3 and 4.
The checkbox 2 let you export the Hull of the parts, which can be very handy if you want to clearly see the baseplates or the track sections to count them and set up your layout quickly the day of the Event.
Exporting a Layout as an Image can be handy when you do not, or can not print your layout and you need to show your layout on hardware that either does not have, or cannot support BlueBrick. It is also useful if you want to add your layouts to picture archives (e.g. Online). This feature can be found in the file > export picture... menu or simply by pressing CTRL+E.
The options window gives you the possibility to select the section of your layout which you want to have exported. Simply click and drag the mouse over the image to place a red frame around the area you want to export. You can make a more precise selection by modifying the "Area Size in Studs" values 5.
You can also enter the required dimensions of the resulting picture. This let you control the level of details that you want in your exported picture. In the "Image Size in Pixel" 6 section, you can either type in the resolution, i.e. how many pixels for drawing one stud (knowing that the native resolution of BlueBrick is 8 pixels per stud, so if you go above that value, you won't have more details in the exported image), or the size of the exported image. Note that each time you type in one of the three values, the two others may be recomputed automatically as they are linked. For example the higher is your pixel/stud resolution, and the bigger the image will be; or if you specify a fixed size, BlueBrick will recompute the needed resolution to fit the layout in that size.
Supported file types are .bmp, .jpg, .gif and .png. Currently BlueBrick doesn't know how to export in one step very large layouts in multiple images with a fixed resolution. And the maximum image size allowed by BlueBrick is 4096 x 4096 pixels. But you can do it manually by exporting multiple times, and selecting each part with the red frame, then reassembling the images in your favorite image editor software.
Printing the layout can be done by printing the image you saved using the "Export picture..." feature. You can open the picture using the standard picture viewing software provided with your operating system and print it from there.