"Other jobs"
Most of the other jobs are just filler so that not everyone is the few jobs that have uses, some might be for interacting with the female player character.
"I can't figure out what type of NPC able to create drug den"
You are offering to make them your slave/slut who works for you for drugs.
The code syntax may be bad as it doesn't have a lot of the brackets i expect but a quick read says:
Can't be married, a lot of females are married, no clue about men as I haven't met many that aren't university classmates.
Females can't be from rich families.
Males can't be sissy, nerd or quiet type, may also not be interested if they are in a successful career already like doctor.
I don't know if they are enabled but you won't convince members of other gangs to work for you/your gang for drugs.
"How can my stuff repay their caused debts? (Im not enough dominant for this to ask?)"
You need to be a gangleader, I have a hard time decyphering what you need from a candidate to form a gang but they need to be your friend and the player needs 5000 money or a pistol or to know the npc is already a criminal but they can't be a member of a different gang if that is enabled.
"I found empty the prosecutor's office, and the courtyard. It's functioning? Somewhere a hidden trick?"
Does not appear to be functioning, the area where functions would go is currently an empty code of during work hours nothing or if it is after workhours do nothing. The police station has some functions that you would expect from the prosecutor or courthouse.
"Can somehow 'recall' my dealers from jail (or cut ties and forget)?"
Are they your dealers or just people you know who are addicts?
If someone is your slave/slut I believe you can go to the police station on the day they were arrested and bribe a cop for their release. In theory it works for up to 10 days afterwards but if it is not the first day you might need to also be friends with a cop or the cheif of police.
"What's the required score in Nudist beach for success?"
If it is saying that she looks at your body and you are too loose then you need to have essentially no body fat and be fairly muscular. I think you need to eat good food and excercise all day. If you did the nerd start you might be very fat and very weak to begin with.
There is a chance the girl just isn't interested in being chatted to but I think it is fairly rare. You may get a lot of married women tho.
"Clothing has role in game? If has why cant be changing on my male PC, only can wear nonweared "
Clothing has minor effect on the males and is mostly for the female player or npcs.
Males: You get a bonus to attractiveness if you dress in the entire businessman set.
Jacket (a few colors), Shirt(a few colors), Trousers (a few colors or plaid pants), Elegant men's shoes (just the one choice).
Female: Different clothing and outfit combos effect a few different scores that determine if you are stylish also a balance of classy or slutty.