1. I've heard some people report the same, apparently in combination with holding down the crtl button.
I'll see if if can replicate this behavior.
2) You need to interact with the counter, not the actually assistant. To continue you don't actually have to talk to her just continue thought the door into the studio.
3&4) Never heard of these before. Please make sure your text speed setting is set to normal instead of instant.
Not being able to interact seems buggy. Also make sure to interact with the counter in front of him instead of the npc!
The game was designed with KB controls in mind and I only recently added the mouse script. When using the keyboard is makes sense to just stand before the counter not having to needlessly walking around a counter to interact with the npc.
to 1) - didn't use CTRL - just pressed a key or clicked (tried different methods) Mia saw her, it goes back to the RPGM-Style-Screen (Overview of the floor) you see her speed across the hall until she stops in front of the wall of her room (not in front of the door). And then only the music continues to play, no reaction to any key you use or any mouse button you click. Only method is to close the window or to kill the task in the taskmanager when in full screen mode
to 2) You need to talk to the assistant - when walking at the door you get a message that you should speak with the assistant. After that point you can ignore her.
to 2-4) checked and found the trigger points - they are very tiny. I clicked on the counter before your posting and I tried again after that in every mm and for example in the supermarket it's not the whole counter, it's only a tiny dark spot in front of the guy. And sorry when I go in a shop to buy something I talk to the employee not to the counter, like every person does. It's counterintuitive.
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Found a bug(?) or it's something RPGM does. Don't know. I you are in one of the move circles like the ones in the photostudio or in the clothes shop employee area, doesn't matter which, you can't move with the mouse.
And I found a design mismatch of an event in the clothing store. When you have the gym quest and need to buy the shorts and T-Shirt Mike is "Shop attendant" and does not know May even if you work for him. Shouldn't that be included in the shopping sub menu in the communications with Mike ?