For info, trying to create a new set comes up with these errors:

3x ...rfaceBetterWardrobe/Modules/SavedOutfits.lua:69: attempt to index field 'button1' (a nil value)
[BetterWardrobe/Modules/SavedOutfits.lua]:69: in function 'OnShow'
[Blizzard_StaticPopup/StaticPopup.lua]:559: in function 'StaticPopup_OnShow'
[Blizzard_StaticPopup_Game/GameDialog.lua]:666: in function <...faceBlizzard_StaticPopup_Game/GameDialog.lua:665>
[C]: in function 'Show'
[Blizzard_StaticPopup/StaticPopup.lua]:390: in function <Blizzard_StaticPopup/StaticPopup.lua:277>
[C]: ?
[C]: in function 'StaticPopup_Show'
[BetterWardrobe/Modules/SavedOutfits.lua]:577: in function 'ShowPopup'
[BetterWardrobe/Modules/SavedOutfits.lua]:740: in function 'ContinueWithSave'
[BetterWardrobe/Modules/SavedOutfits.lua]:704: in function 'EvaluateSaveState'
[BetterWardrobe/Modules/SavedOutfits.lua]:685: in function 'EvaluateAppearances'
[BetterWardrobe/Modules/SavedOutfits.lua]:605: in function 'StartOutfitSave'
[BetterWardrobe/Modules/SavedOutfits.lua]:261: in function <...rfaceBetterWardrobe/Modules/SavedOutfits.lua:256>
[tail call]: ?
[C]: in function 'securecallfunction'
[Blizzard_Menu/Menu.lua]:896: in function 'Pick'
[Blizzard_Menu/MenuTemplates.lua]:74: in function <Blizzard_Menu/MenuTemplates.lua:68>

Locals:
self = StaticPopup1 {
ProgressBarSpacer = Texture {
}
TopSpacer = FontString {
}
Buttons =

{
}
visibleButtons = {
}
CoverFrame = Frame {
}
AlertIcon = Texture {
}
widthPadding = 0
BG = Frame {
}
ProgressBarFill = Texture {
}
ProgressBarBorder = Texture {
}
dirty = false
ButtonContainer = Frame {
}
which = "BW_NAME_TRANSMOG_OUTFIT"
hideOnEscape = 1
SubText = FontString {
}
ItemFrame = Frame {
}
DarkOverlay = Frame {
}
minimumWidth = 297.136000
declineTimeLeft = 0
MoneyInputFrame = StaticPopup1MoneyInputFrame {
}
EditBox = StaticPopup1EditBox {
}
previousRegionKey = "ButtonContainer"
Dropdown = Button {
}
Spinner = Frame {
}
dialogInfo = {
}
numButtons = 2
timeleft = 0
MoneyFrame = StaticPopup1MoneyFrame {
}
Text = StaticPopup1Text {
}
ExtraButton = StaticPopup1ExtraButton {
}
CloseButton = StaticPopup1CloseButton {
}
Separator = Texture {
}
heightPadding = 16
}
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to index field 'button1' (a nil value)"

and:

15x ...rfaceBetterWardrobe/Modules/SavedOutfits.lua:83: attempt to index field 'editBox' (a nil value)
[BetterWardrobe/Modules/SavedOutfits.lua]:83: in function 'EditBoxOnTextChanged'
[Blizzard_StaticPopup/SharedTemplates.lua]:66: in function <...faceBlizzard_StaticPopup/SharedTemplates.lua:62>

Locals:
self = StaticPopup1EditBox {
owningDialog = StaticPopup1 {
}
hasAutoComplete = false
Instructions = FontString {
}
autoCompleteParams =

{
}
baseWidth = 130
NineSlice = Frame {
}
desiredWidth = 130
useScaleWeight = true
addHighlightedText = true
baseHeight = 24
layoutType = "TooltipDefaultLayout"
}
parent = StaticPopup1 {
ProgressBarSpacer = Texture {
}
TopSpacer = FontString {
}
Buttons = {
}
visibleButtons = {
}
CoverFrame = Frame {
}
AlertIcon = Texture {
}
widthPadding = 0
BG = Frame {
}
ProgressBarFill = Texture {
}
ProgressBarBorder = Texture {
}
dirty = false
ButtonContainer = Frame {
}
which = "BW_NAME_TRANSMOG_OUTFIT"
hideOnEscape = 1
SubText = FontString {
}
ItemFrame = Frame {
}
DarkOverlay = Frame {
}
minimumWidth = 297.136000
declineTimeLeft = 0
MoneyInputFrame = StaticPopup1MoneyInputFrame {
}
EditBox = StaticPopup1EditBox {
}
previousRegionKey = "ButtonContainer"
Dropdown = Button {
}
Spinner = Frame {
}
dialogInfo = {
}
numButtons = 2
timeleft = 0
MoneyFrame = StaticPopup1MoneyFrame {
}
Text = StaticPopup1Text {
}
ExtraButton = StaticPopup1ExtraButton {
}
CloseButton = StaticPopup1CloseButton {
}
Separator = Texture {
}
heightPadding = 16
}
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to index field 'editBox' (a nil value)"

And:

3x ...rfaceBetterWardrobe/Modules/SavedOutfits.lua:74: attempt to index field 'editBox' (a nil value)
[BetterWardrobe/Modules/SavedOutfits.lua]:74: in function 'OnHide'
[Blizzard_StaticPopup/StaticPopup.lua]:586: in function 'StaticPopup_OnHide'
[Blizzard_StaticPopup_Game/GameDialog.lua]:677: in function <...faceBlizzard_StaticPopup_Game/GameDialog.lua:676>
[C]: ?
[C]: ?
[C]: in function 'Hide'
[Blizzard_StaticPopup/StaticPopup.lua]:692: in function 'StaticPopup_OnClick'
[Blizzard_StaticPopup_Game/GameDialog.lua]:27: in function <...faceBlizzard_StaticPopup_Game/GameDialog.lua:25>

Locals:
self = StaticPopup1 {
ProgressBarSpacer = Texture {
}
TopSpacer = FontString {
}
Buttons =

{
}
visibleButtons = {
}
CoverFrame = Frame {
}
AlertIcon = Texture {
}
widthPadding = 0
BG = Frame {
}
ProgressBarFill = Texture {
}
ProgressBarBorder = Texture {
}
dirty = false
ButtonContainer = Frame {
}
which = "BW_NAME_TRANSMOG_OUTFIT"
hideOnEscape = 1
SubText = FontString {
}
ItemFrame = Frame {
}
DarkOverlay = Frame {
}
minimumWidth = 297.136000
declineTimeLeft = 0
MoneyInputFrame = StaticPopup1MoneyInputFrame {
}
EditBox = StaticPopup1EditBox {
}
previousRegionKey = "ButtonContainer"
Dropdown = Button {
}
Spinner = Frame {
}
dialogInfo = {
}
numButtons = 2
timeleft = 0
MoneyFrame = StaticPopup1MoneyFrame {
}
Text = StaticPopup1Text {
}
ExtraButton = StaticPopup1ExtraButton {
}
CloseButton = StaticPopup1CloseButton {
}
Separator = Texture {
}
heightPadding = 16
}
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to index field 'editBox' (a nil value)"