Big problems after trying to install Lennarts textures

After trying to get Lennarts texture working I know only get error messages telling me about missing files and then Fs9.1 crashes to the desktop when I try to load a flight.One mistake I'm aware of is that I first directly copied the winter season into the scenery/world folder. Then I found the documentation and tried follow its instruction. Then after using the supplied texture switch utility everything got really messed up. I don't understand what this utility does.Also should I really completely remove the texture folder from scenery/world? I did it was back later. Also the folder for the area I select in texture switch is not present any more in scenery/world.I don't understand this. I tried restoring these folders.How do I best clean up this mess? I also have FScene fall. Must it be reinstalled?