Could you please check what I've done for 2 GC presets: Zanzibar-S and Teramachy? Are they correct?
No, they are missing links. Also, it is not necessary to upload an image for a Game Courier preset, because you can use an image generated by the Diagram Designer. From your preset, choose the Diagram Designer item in the Related Pages menu. This will open the Diagram Designer with an image matching the setup for your game. You can use this image on your page instead of uploading one. You may also wish to use a smaller image on this page. You may do that with the Diagram Designer by reducing its scale.
I have understood that after creating the page for the preset, I have to select "Upload or Manage Files" to upload an image, that in this case is a screen copy of the preset. (as this image is loaded when the preset is launched, why the need to upload an image already available on the site?)
Because it is not available on the site. Game Courier sometimes renders boards as HTML or CSS code, and when it does render boards as images, it stores them in a temporary directory and eventually deletes them. That's where the Diagram Designer comes in. It more or less uses the same code as Game Courier does for rendering boards as images, and it can give you a link for drawing your board.
And there I have to add the image. If I select WYSYWIG, I can attach an image. When I click the button, I am asked to enter the URL. How can I know the URL straight? Too bad it don't offer to me directly the link to the image I have uploaded.
The file manager that is provided for uploading images should be showing you the URL of each image. You may find it convenient to keep it open in a different tab than the one you're writing your text in.
No, they are missing links. Also, it is not necessary to upload an image for a Game Courier preset, because you can use an image generated by the Diagram Designer. From your preset, choose the Diagram Designer item in the Related Pages menu. This will open the Diagram Designer with an image matching the setup for your game. You can use this image on your page instead of uploading one. You may also wish to use a smaller image on this page. You may do that with the Diagram Designer by reducing its scale.
Because it is not available on the site. Game Courier sometimes renders boards as HTML or CSS code, and when it does render boards as images, it stores them in a temporary directory and eventually deletes them. That's where the Diagram Designer comes in. It more or less uses the same code as Game Courier does for rendering boards as images, and it can give you a link for drawing your board.
The file manager that is provided for uploading images should be showing you the URL of each image. You may find it convenient to keep it open in a different tab than the one you're writing your text in.