Still having trouble with this 3D footprint generator. How do I fix it?

I'm trying to make a 3D footprint script but it doesn't seem to do anything. I've already sorted through all the errors I was getting and its not giving me any more. This script detects the distance between players and the surface then if a player is close enough subtracts their legs from the surface. Any help with it would be great.

-- tables --
local DetectDistance = {}
local Char = {}
local Surface = {}
local x = {}

local GlobalFreqency = 10

function GetCharacters()
    local Char = game.Workspace:GetChildren()
    for i=1,#Char do
        if not Char[i]:FindFirstChild("Humanoid") then
            table.remove(Char, i)
        end
    end
end

function GetSurface()
    local Surface = game.Workspace.ImprintableMap:GetChildren()
    for i=1,#Surface do
        for l=1,#Char do
            DetectDistance[l] = (Surface[i].position - Char[l].HumanoidRootPart.Position).magnitude
        end
        DueDistance = math.min(unpack(DetectDistance))
        if DueDistance >= (Surface[i].Size.X + Surface[i].Size.Z)/2 + 5 then
            table.remove(Surface[i])
        end
    end
end

while true do
    wait(1/GlobalFreqency)
    -- Get characters -- 
    local Char = game.Workspace:GetChildren()
    for i=1,#Char do
        if not Char[i]:FindFirstChild("Humanoid") then
            table.remove(Char, i)
        end
    end
    -- Get Surfaces --
    local Surface = game.Workspace.ImprintableMap:GetChildren()
    for i=1,#Surface do
        for l=1,#Char do
            DetectDistance[l] = (Surface[i].position - Char[l].HumanoidRootPart.Position).magnitude
        end
        DueDistance = math.min(unpack(DetectDistance))
        if DueDistance >= (Surface[i].Size.X + Surface[i].Size.Z)/2 + 5 then
            table.remove(Surface[i])
        end
    end
    -- Im guessing this part is broken --
    if DetectDistance ~= nil and math.min(Surface.TriangleCount) <= 4980 then
        for i=1,#Char do
            for l=1,#Surface do
                x[1] = Char[i].LeftFoot:clone()
                x[1]:ClearAllChildren()
                x[1].name = "CharSub" .. i + l
                x[1].parent = game.Workspace.ImprintableMap
                x[2] = Char[i].LeftLowerLeg:clone()
                x[2]:ClearAllChildren()
                x[2].name = "CharSub" .. i + l + 1
                x[2].parent = game.Workspace.ImprintableMap
                x[3] = Char[i].LeftUpperLeg:clone()
                x[3]:ClearAllChildren()
                x[3].name = "CharSub" .. i + l
                x[3].parent = game.Workspace.ImprintableMap
                x[4] = Char[i].RightFoot:clone()
                x[4]:ClearAllChildren()
                x[4].name = "CharSub" .. i + l
                x[4].parent = game.Workspace.ImprintableMap
                x[5] = Char[i].RightLowerLeg:clone()
                x[5]:ClearAllChildren()
                x[5].name = "CharSub" .. i + l + 1
                x[5].parent = game.Workspace.ImprintableMap
                x[6] = Char[i].RightUpperLeg:clone()
                x[6]:ClearAllChildren()
                x[6].name = "CharSub" .. i + l
                x[6].parent = game.Workspace.ImprintableMap
                local Imprint = Surface[l]:SubtractAsync(x)
                Imprint.name = "SnowPlane"
                Imprint.parent = game.Workspace.ImprintableMap
            end
        end
    end
end