Hey Tamara! Thank you for the feedback and the reports!
I will make update to solve that problems. Even if it's just for you and me!

About Melus...
Spoiler Well, he's the most interesting in that quest because he apparently doesn't have money to pay you. So you have a choice of giving him the groceries or refuse to give him. If you give him you get a nice reward. Since you're unable to speak with him, use console:
set wwDelivery04.Melus 1
[color=#000000;background:#000000], for giving him the groceries or
set wwDelivery04.Melus 2
,
Alternatively, if that doesn't work for you:
SetStage wwDelivery04 30
You don't have to use capital letters.[/color]
Alternative location and original location are identical in everything save the position of stand. I'm not sure why don't you see stuff on the stand. It's controlled like this:
Domenick comes to the stand before 8 am, at 8 am he activates the sign and the stuff should be there. At 5 pm, he activates the sign again and the stuff is gone. Sometimes used to happen that Domenick would go crazy and it was all upside down; the stuff was there over night instead during day. That's why I have made another script that checks that and turns it off if it's on during the night.

He will sell things anyway between 8 and 17 because his stash in in the secret underground container, the things on the stand are just activators for immersion.
You have two more quests after
You'll get the message after you finish all the quests.
I'm interested, what was your choice with
?