How in the world, this keeps erroring? [PLEASE HELP!]

Well I made this door that activates with spacebar once the players torso is touching the part defined, but the thing is the script will run find the door will open and close, but 2 things the user can "spam" the spacebar and break it and once the script runs once and i try to run it again it jitters and won't slide the right way, here is the link?

www.roblox.com/SH-item?id=163931688

local open = script.Parent.Parent.DoorPart.Open
local close = script.Parent.Parent.DoorPart.Closed

if script.Running.Value == true then
return end
script.Running.Value=true
while true do wait(0.1)
if open.Value == false then
    print"Open"
    for i = 1, 4.9, 0.1 do
        script.Parent.CFrame=script.Parent.CFrame*CFrame.new(0.2,0,0)
        wait()
        wait(WaitTime)
    open.Value=true
    close.Value=false
    end
    wait(3)
else if open.Value == true then
    while true do wait(0.1)
        if open.Value == true then
            print"Close"
            for i = 1, 4.9, 0.1 do
                script.Parent.CFrame=script.Parent.CFrame*CFrame.new(-0.2,0,0)
                wait()
                wait(WaitTime)
                open.Value=false
                close.Value=true
                script.Disabled=true
                script.Running.Value=false
                wait()
            end
        end
    end
end
end
end
----DoorScript

local PLR = game.Players.LocalPlayer
PLR.Character["Torso"].Touched:connect(function(hit)
    if hit.Name == "DoorOpen" then
 game.Players.LocalPlayer:GetMouse().KeyDown:connect(function(key)
  if key == " " then
   if hit.Parent.DoorPart.Script.Running.Value ~= false and hit.Parent.DoorPart.Open.Value ~= false then
    print"OpenWithLocalScript"
hit.Parent.DoorPart.Script.Disabled=false
wait(5)
hit.Parent.DoorPart.Script.Disabled=true
else
    if hit.Parent.DoorPart.Script.Running.Value ~= true then
    return end
end
end
end)
    end
end)

Door control script