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With no disrespect meant. I can understand why this may be frustrating for you. But knowing the link or site you have stated no longer works. Then would it not be best advised that you just ask for the post to be removed, so as to stop the dislikes coming?
When you download anything for OMSI most of the time you get a folder inside the download called "OMSI 2". What I do is open that folder up then copy and paste its contents directly in the main directory for OMSI. This then merges all files with the same name with each other meaning there's no possible way a file could go to the wrong place.
Dragging files you have downloaded and putting them into the maps folder isn't the right thing to do. For example In the last screenshot of yours, there are splines missing. When you have downloaded the correct content you should then paste them into the main directory, as the download will merge with the splines folder OMSI has.