here is the error from BugSack:

1x Interface/AddOns/MCL/functions.lua:329: attempt to index field 'overview' (a nil value)
[string "@Interface/AddOns/MCL/functions.lua"]:329: in function UpdateCollection' [string "@Interface/AddOns/MCL/main.lua"]:73: in function Toggle'
[string "@Interface/AddOns/MCL/Core.lua"]:17: in function ?' [string "@Interface/FrameXML/ChatFrame.lua"]:5224: in function ChatEdit_ParseText'
[string "@Interface/FrameXML/ChatFrame.lua"]:4888: in function ChatEdit_SendText' [string "@Interface/FrameXML/ChatFrame.lua"]:4924: in function <Interface/FrameXML/ChatFrame.lua:4920> [string "=[C]"]: in function ChatEdit_OnEnterPressed'
[string "*ChatFrame.xml:127_OnEnterPressed"]:1: in function <[string "*ChatFrame.xml:127_OnEnterPressed"]:1>

Locals:
self =

{
UpdateCollection = defined @Interface/AddOns/MCL/functions.lua:276
LinkMountItem = defined @Interface/AddOns/MCL/functions.lua:115
TableMounts = defined @Interface/AddOns/MCL/functions.lua:24
getTableLength = defined @Interface/AddOns/MCL/functions.lua:107
CreateMountsForCategory = defined @Interface/AddOns/MCL/functions.lua:180
GetMountID = defined @Interface/AddOns/MCL/functions.lua:234
getFaction = defined @Interface/AddOns/MCL/functions.lua:11
CreateBorder = defined @Interface/AddOns/MCL/functions.lua:93
initSections = defined @Interface/AddOns/MCL/functions.lua:34
TestFunction = defined @Interface/AddOns/MCL/functions.lua:103
}
(*temporary) = defined @Interface/AddOns/MCL/functions.lua:254
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to index field 'overview' (a nil value)"
clearOverviewStats = defined @Interface/AddOns/MCL/functions.lua:270
core = {
MCL_MF_Nav = Nav {
}
stats = {
}
MCL_MF = MCLFrame {
}
sectionNames = {
}
overviewStats = {
}
Frames = {
}
collected = 0
mounts = {
}
total = 0
Main = {
}
sectionFrames = {
}
sections = {
}
overviewFrames = {
}
Function = {
}
mountList = {
}
}

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