I know that there are two post like this one in Stackoverflow (this and this) but I already tried what is described there without any result and I have the feeling that I'm running out of options.
This screenshot is from one of these two posts, but is exactly what I also see.
In my case, I was never able to make the googlemaps work and I tried to import and copy the stuff in so many different ways that I guess is what lead to the actual situation. In my last attempt, I was going to try to follow the steps described in this post, which seems to be the most accurate one, but as I said, now I just can't import the google-play-services_lib because keeps telling me that is in use. I made sure that I deleted the project from my workspace and any other place where it could be stored by searching for it.
Does anyone have an idea that is not described in the other two posts? Creating a new workspace and importing my project and then the google-play-services_lib could be a solution or the problem is of another nature? Is there a way of obtaining more information about the error shown by Eclipse in order to fix it?