I ran into this error myself. It's been broken since the last patch.
Here's what the error text says.
1x WIM-3.3.7\Modules\ShortcutBar.lua:324: attempt to index global 'win' (a nil value)
WIM-3.3.7\Modules\ShortcutBar.lua:52: in function <WIM\Modules\ShortcutBar.lua:50>
Locals:
self = WIM_ShortcutBarButton8 {
parentWindow = WIM3_msgFrame2 {}
SetDefaults = <function> @ WIM\Modules\ShortcutBar.lua:55:
index = 4
isEnabled = true
Enable = <function> @ WIM\Modules\ShortcutBar.lua:24:
0 = <userdata>
icon = <unnamed> {}
Disable = <function> @ WIM\Modules\ShortcutBar.lua:29:
}
button = "LeftButton"
buttons = <table> {
1 = <table> {}
2 = <table> {}
3 = <table> {}
4 = <table> {}
}
---