[LUA]Mining Turtle Program

Hi guys,
I'm triying to make a program to make a mining turtle automaticly mining a predefined area but I'm having some issues like if I want to mine an area 5x5 it actually mine a 5x6

http://pastebin.com/re4yeHcc

Other problems are the commands that need to be written twice for it to take them and that this part

			UnloadLayer = UnloadLayer + 1
			if (UnloadLayer == UnloadTargetLayer) and (Layer ~= TargetLayer)  then
				Unload(1)
			elseif Layer == TargetLayer then
				Unload(0)
			else
				turtle.down()
				for i=0,1 do
					if turtle.detectDown() then
						turtle.digDown()
					end
					turtle.down()
				end
			end

seem to not execute at all.
Thanks in advance for anyone willing to help me.

Place debug prints before and after conditionals you believe should execute but don't.

Yes I tested it again and it doesn't execute that part. It always does the last statement no matter what wich is:

   else
	   turtle.down()
	   for i=0,1 do
		   if turtle.detectDown() then
			   turtle.digDown()
		   end
		   turtle.down()
	   end
   end

Sorry, a debug print looks like this:

print(type(UnloadLayer),": ",UnloadLayer,type(UnloadTargetLayer),": ",UnloadTargetLayer,type(Layer),": ",Layer,type(TargetLayer),": ",TargetLayer)

You put it before the conditional that isn't working as you want and it helps you figure out why.

In this case, it is because UnloadLayer is a number and UnloadTargetLayer is a literal string that may or may not contain numeric characters depending on what the user entered.