The このままで in このままでいいんだよ。 modifies the いい adverbially, meaning "It's okay to be just the way you are / just the way we are / It's okay to let it just the way it is", whereas the このままで in いかないで。このままで。 means このままでいてください。(≒ Please stay where you are. / Please stay just as you are.), いてください being left unsaid/implied.

このままで is written in Hiragana in the modern Japanese.

The このままで in このままでいいんだよ。 modifies the いい adverbially, meaning "It's okay to be just the way you are / just the way we are / It's okay to let it just the way it is", whereas the このままで in いかないで。このままで。 means このままでいてください or このままでいさせてください。(≒ Please stay where you are. / Please stay just as you are / Let us be just the way we are), いてください/いさせてください being left unsaid/implied.

このままで is written in Hiragana in modern Japanese.

The このままで in このままでいいんだよ。 modifies the いい adverbially, meaning "It's okay to be just the way you are", whereas the このままで in いかないで。このままで。 means このままでいてください。(≒ Please stay where you are. / Please stay just as you are.), いてください being left unsaid/implied.

このままで is written in Hiragana in the modern Japanese.

The このままで in このままでいいんだよ。 modifies the いい adverbially, meaning "It's okay to be just the way you are / just the way we are / It's okay to let it just the way it is", whereas the このままで in いかないで。このままで。 means このままでいてください。(≒ Please stay where you are. / Please stay just as you are.), いてください being left unsaid/implied.

このままで is written in Hiragana in the modern Japanese.