I followed the advice in this question to rename my ASP.NET Identity tables:
modelBuilder.Entity().ToTable(\"UserClaim\");
modelBuilder.
You should skip the following line, then it works perfectly well:
modelBuilder.Entity().ToTable("User");
So the only mapping you need is:
modelBuilder.Entity().ToTable("UserClaim");
modelBuilder.Entity().ToTable("UserRole");
modelBuilder.Entity().ToTable("UserLogin");
modelBuilder.Entity().ToTable("Role");
modelBuilder.Entity().ToTable("User");
Hope that helps.