Items isn t spawn in enderchest

[AKRODOGY]

I have that skript

variables:
    {rewards::1} = emerald
    {rewards::2} = diamond
    {rewards::3} = apple

command /admin [<text>] [<text>] [<text>]:
    trigger:
        if the arg-1 is "crate":
            if the arg-2 is "set":
                if arg-3 is "1" or "2" or "3" or "4" or "5" or "6" or "7" or "8" or "9" or "10" or "11" or "12" or "13" or "14" or "15":
                    set {location.%arg-3%.chestspawn} to player's location
                    send "Chestspawn %arg-3% created."
                 
every 1 minute:
    set {_random} to a random integer between 1 and 3
    set block at {location.%{_random}%.chestspawn} to ender chest named "&cLootCrate"
    broadcast "Chest spawned at %{location.%{_random}%.chestspawn}%"
    set {_random2} to a random integer between 4 and 7
    set block at {location.%{_random2}%.chestspawn} to ender chest named "&cLootCrate"
    broadcast "Chest spawned at %{location.%{_random2}%.chestspawn}%"
    set {_random3} to a random integer between 8 and 10
    set block at {location.%{_random3}%.chestspawn} to ender chest named "&cLootCrate"
    broadcast "Chest spawned at %{location.%{_random3}%.chestspawn}%"
    set {_random4} to a random integer between 11 and 13
    set block at {location.%{_random4}%.chestspawn} to ender chest named "&cLootCrate"
    broadcast "Chest spawned at %{location.%{_random4}%.chestspawn}%"
    set {_random5} to a random integer between 14 and 15
    set block at {location.%{_random5}%.chestspawn} to ender chest named "&cLootCrate"
    broadcast "Chest spawned at %{location.%{_random5}%.chestspawn}%"
         
 on rightclick:
    loop integers between 1 and 15:
        clicked block's location is {location.%loop-number%.chestspawn}
        cancel event
        if {LootCrate.open} is true:
            message "&cSomeone else opened this crate already" to player
            stop
        else:
            set {LootCrate.open} to true
            wait 0.5 seconds
            give player a random item out of {rewards::*}
            launch burst firework colored blue at clicked block timed 0.1
            wait 0.5 seconds
            set {LootCrate.open} to false

The problems are:

1.The items aren t spawn in enderchest
2.The name from enderchest are "Ender Chest" and not "&cLootChest)"
3.Firework not work

And i dont know :
1.I want to run this skript when is 5players or more?
2.How can i put a item in enderchest with a name and a lore ex : a diamond sword named "&cExtra" with lore "Magic for you"?

WARNING : I WANT A EXAMPLE EX: (if the player is op: ) NOT SOME WORDS WITH WHAT ARE YOU WANT TO EXPLAIN, THE CODE I WANT