Repairing Precision Alignment

1. Replacing Alt and Shift keys:

Alt key:
Where you can find this:
ui.lua
Lines: 701, 1702 (before editing)

local alt = LocalPlayer():KeyDown( IN_WALK )
replace with:
local alt = input.IsKeyDown(81)
------------------------------------
Shift key
Where you can find this:
ui.lua
Line: 1701 (before editing)
prop_functions.lua
Lines: 53, 91, 1113 (before editing)
local shift = LocalPlayer():KeyDown( IN_SPEED )
replace with:
local alt = input.IsKeyDown(79)

2. Fixing a bug that occurs when you try to stack a prop over a limit, it breaks whole stacking function, justly the tool stacks over the limit, it doesn't have any limit.

Function that checks if you can spawn entity (tweak it to the server needs, I tested it on Sandbox using CVAR as limit + NPP)
------------------------------------
local function CanSpawnEnt(user)
	local MaxProps = cvars.Number("sbox_maxprops",0)
	local ThingsUnfiltered = ents.GetAll()
	local Filtered = {}
	local CheckFor = {"gmod_button","keypad","keypad_advanced","prop_physics"} -- afaik the buttons etc. are counted as props on server

	for _,Thing in ipairs(ThingsUnfiltered) do
		for i,Class in pairs(CheckFor) do
			if(Thing:GetClass() == Class&&NADMOD.PropOwners[Thing:EntIndex()] == LocalPlayer():Nick()) then
				table.insert(Filtered,Thing)
			end
		end
	end
	local ThingsCount = table.Count(Filtered)
	return (ThingsCount < MaxProps)
end
-----------------------------------
Add the function to prop_functions.lua
You can put it almost everywhere, mine starts at line 14

Now you need to actually stop spawning the entity, it's pretty easy
Jump to line 55, add something similar to this:

-----------------------------------
if shift then
	if(!CanSpawnEnt()) then
		Warning("Attempted to stack over prop limit")
		return false
	end
stack = GetConVarNumber( PA_.."stack_num")
...
...
-----------------------------------