I lvl'ed up Aht to lvl 6, had his event but it's doesn't trigger Yuela's measurement event.

Also I couldn't trigger emelita's measurement event either.


Are there special requirements for those?

make them a costume?

otherwise you should automatically get them in like chapter 6

I can't wait to chapter six, having that scene is a requirement for Yuela's route wich locks up in chapter 2

According to Aroduc leveling up Aht to lvl 6 should trigger it but still nothing

I had the same problem.
You have to talk to your allies in the workshop, by klicking on them when they have a star over their head.