First Problem is "Requested module experienced an error while loading"

local SkinModule = require(game.ServerScriptService:WaitForChild("ModuleScript"))

script.Parent.ClickDetector.MouseClick:Connect(function(player)
	
	if player.leaderstats.Cash.Value >= 500 then
		
		local Skin = SkinModule.." selected"
		
		game.ReplicatedStorage.OpenCrate:FireClient(player,Skin)
	end
end)

Second is "ServerScriptService.Saves:5: attempt to index nil with 'Cash' "

local DS = game:GetService("DataStoreService"):GetDataStore("SaveData")
game.Players.PlayerAdded:Connect(function(plr)
	wait()
	local plr = "id_"..plr.userId
	local save1 = plr.leaderstats.Cash
	local save2 = plr.leaderstat.BUX
	
	local GetSaved = DS:GetAsync(plr)
	if GetSaved then
		save1.Value = GetSaved[1]
		save2.Value = GetSaved[2]
	else
		local NumberForSaving = {save1.Value, save2.Value,}
		DS:GetAsync(plr, NumberForSaving)
		end
end)

game.Players.PlayerRemoving:Connect(function(plr)
	DS:SetAsync("id_"..plr.userId,{plr.leaderstats.Cash.Value, plr.leaderstats.BUX.Value,})
end)

Leaderstats script

local Cash = Instance.new("IntValue")

	Cash.Value = 0

	Cash.Name = 'Cash'

	Cash.Parent = leaderstats
AnonymousEdited