1) Is make up completely haram in front of non mahram or is light make up accepted.

2) I am aware that nail polish in front of non mahram is haram but what about long natural nails? (by "long" i mean that the white part of the nail is around 1cm long)?

1) Yes it is completely haram in front of non mahram.

2) You are aware of the intention and that is to beautify and it is haram to show to na mahram.