Lots of people play on 1.17.1, so it would be recommended. Although if you wanna keep 1.18.2, I think using both Vault and EssentialX will provide an economy.
This usually happens when your skript version isn't supported by your server version (i.e. a 2.6 skript version on a 1.19 server). Try downloading the first version of skript that supports your server version.
Try this:
on death:
if victim is a zombie:
clear drops
chance of 50%:
set {_drop} to diamond named "&9Custom Drop"
drop {_drop} at victim's location
stop
chance of 50%:
set {_amount} to random integer between 1 and 3
set {_drop} to {_amount} of iron ingot named "&9Custom Drop"
drop {_drop} at victim's location
Make a 64x64 image file and name it server-icon. It must be in a .png format. From there, upload the image file to your server and restart. You may need to reload the server list for it to take effect.
You can use skript to teleport the player facing a certain direction when they join. Replace X Y and Z with your coords and the world name to... your world name.
on join:
wait 1 tick
teleport player to location(X, Y, Z, world("world"), -90, 0)
There could be a couple of reasons.
1. Your selection size is too big for WorldEdit to process (in which case, replace WorldEdit with FastAsyncWorldEdit)
2. Your WorldEdit may not be supported by your current server version.
check /sk info. If it still says 2.6.2, check the Addons tab and delete skript from there (Make sure to save your scripts to your desktop). Then restart. Add the 2.6 skript.jar to your plugins file and restart again. Go to the skript file and readd all your skripts, then /sk reload all