Seems I was right. Without the libpng-dev installed, Image::Scale installed succesfuly, although without jpeg support. I'm not sure if that affects LMS.
Maybe someone makes a package for libpng and libpng-dev 1.4.x one day.
As for the eglibc_base-dev issue:
eglibc_base-dev is not in the Pi Repo, and glibc_base-dev is installed. So I´m not sure whats going on here.
Once all modules are installed, I´ll report back how it goes. DBIx::Class just took all night to compile