i found this post
https://forum.unity.com/threads/standard-unity-2d-character-script-not-working-with-surface-effector-2d.441527/
An doing the change suggested seem to work...
Change 1 to 2 in the PlataformerCharacter2D.cs
1) m_Rigidbody2D.velocity = new Vector2(move*m_MaxSpeed, m_Rigidbody2D.velocity.y);
2) m_Rigidbody2D.AddForce(move * m_MaxSpeed * Vector2.right, ForceMode2D.Impulse);
BUT the controller stops working fine for movement, since the speed keeps increasing
what would be the proper change?
The second method can work, but you need to tweak the speed settings of the controller and possibly the mass/drag of the rigidbody in order to get something similar as up above. I don't have a lot of experience working with 2D Controllers so it's something you'll need to test out to determine what works best for your characters.