Entity-Framework 5.0 with PostgreSQL
You shouldn't be generating the ssdl, msl, csdl files. These files are only required if you want to use the designer. Delete these files and the generated ObjectLayer.cs.
You should also not be using an EntityClient connection string. Update your connection string to simply be the following.
<connectionStrings> <add name="PostGreSQL" providerName="Npgsql" connectionString="Server=asdf;Port=5432;User Id=asdf;Password=asdf;Database=asdf;enlist=true" /></connectionStrings>