Script Discussion - S07E01!

Maybe have him loitering about near her now and then, in a way that might or might not be seen as a bit odd. As in, he might have a reason to be there, but kinda lingers a bit more than normal, or watches Idril a bit more than normal.
In Ep1 Idril and Maeglin are portrayed as Turgon's inner inner sanctum (they enter and leave with him, for example). I also have them sitting together although not really interacting with each other. My feeling was that the disturbing feelings that Maeglin has regarding Idril will really only come to the surface when there is cause (from his perspective) for jealousy. This is not the case in Ep1 where Idril is not showing particular interest in any of the humans (or vice versa). We can make it clear that Idril is not great friends with Maeglin from her body language, but I don't see opportunity for relevantly showing Maeglin staring at Idril, or loitering.

The Episode is trying to stay focused on introducing Húrin, Huor (and Handir) as characters and to present the story mostly from their perspective.

So the script has Maeglin say a couple of unpleasant things but not really out of the ordinary for an Elf who is not all that interested in humans. I've always interepreted this stage of Maeglin's story as one where he really is a loyal citizen of Gondolin, with his own band of miners and craftspeople, and of course he does some heroic things in the upcoming battle.
Definitely need to not get sidetracked at this point. One might imagine our hypothetical director suggesting small things to the hypothetical Maeglin actor, but nothing super obvious that needs scripting.