diff --git a/AceConfig-3.0/AceConfigDialog-3.0/AceConfigDialog-3.0.lua b/AceConfig-3.0/AceConfigDialog-3.0/AceConfigDialog-3.0.lua
index e758beb..19772f0 100644
--- a/AceConfig-3.0/AceConfigDialog-3.0/AceConfigDialog-3.0.lua
+++ b/AceConfig-3.0/AceConfigDialog-3.0/AceConfigDialog-3.0.lua
@@ -2014,28 +2014,37 @@ function AceConfigDialog:AddToBlizOptions(appName, name, parent, ...)
 		group:SetCallback("OnHide", ClearBlizPanel)
 
 		local categoryName = name or appName
-		if parent then
-			local parentID = BlizOptionsIDMap[parent] or parent
-			local category = Settings.GetCategory(parentID)
-			if not category then
-				error(("The parent category '%s' was not found"):format(parent), 2)
-			end
-			local subcategory = Settings.RegisterCanvasLayoutSubcategory(category, group.frame, categoryName)
-			group:SetName(subcategory.ID, parentID)
-		else
-			if BlizOptionsIDMap[categoryName] then
-				error(("%s has already been added to the Blizzard Options Window with the given name: %s"):format(appName, categoryName), 2)
-			end
+		-- CoA-compat: the Settings.* API (GetCategory / RegisterCanvasLayoutCategory /
+		-- RegisterCanvasLayoutSubcategory / RegisterAddOnCategory) is a retail-only
+		-- (Dragonflight+) replacement for the WotLK-era InterfaceOptions_AddCategory.
+		-- On the 3.3.5-based CoA client Settings is nil, so fall back to the legacy API.
+		if Settings and Settings.GetCategory then
+			if parent then
+				local parentID = BlizOptionsIDMap[parent] or parent
+				local category = Settings.GetCategory(parentID)
+				if not category then
+					error(("The parent category '%s' was not found"):format(parent), 2)
+				end
+				local subcategory = Settings.RegisterCanvasLayoutSubcategory(category, group.frame, categoryName)
+				group:SetName(subcategory.ID, parentID)
+			else
+				if BlizOptionsIDMap[categoryName] then
+					error(("%s has already been added to the Blizzard Options Window with the given name: %s"):format(appName, categoryName), 2)
+				end
 
-			local category = Settings.RegisterCanvasLayoutCategory(group.frame, categoryName)
-			if not (C_SettingsUtil and C_SettingsUtil.OpenSettingsPanel) then
-				-- override the ID so the name can be used in Settings.OpenToCategory
-				-- unfortunately with incoming API changes in 12.0 (and likely classic at some point) this override is no longer possible
-				category.ID = categoryName
+				local category = Settings.RegisterCanvasLayoutCategory(group.frame, categoryName)
+				if not (C_SettingsUtil and C_SettingsUtil.OpenSettingsPanel) then
+					-- override the ID so the name can be used in Settings.OpenToCategory
+					-- unfortunately with incoming API changes in 12.0 (and likely classic at some point) this override is no longer possible
+					category.ID = categoryName
+				end
+				group:SetName(category.ID)
+				BlizOptionsIDMap[categoryName] = category.ID
+				Settings.RegisterAddOnCategory(category)
 			end
-			group:SetName(category.ID)
-			BlizOptionsIDMap[categoryName] = category.ID
-			Settings.RegisterAddOnCategory(category)
+		else
+			group:SetName(name or appName, parent)
+			InterfaceOptions_AddCategory(group.frame)
 		end
 
 		return group.frame, group.frame.name
diff --git a/AceGUI-3.0/widgets/AceGUIContainer-BlizOptionsGroup.lua b/AceGUI-3.0/widgets/AceGUIContainer-BlizOptionsGroup.lua
index d95db58..4f635d8 100644
--- a/AceGUI-3.0/widgets/AceGUIContainer-BlizOptionsGroup.lua
+++ b/AceGUI-3.0/widgets/AceGUIContainer-BlizOptionsGroup.lua
@@ -99,7 +99,11 @@ local methods = {
 Constructor
 -------------------------------------------------------------------------------]]
 local function Constructor()
-	local frame = CreateFrame("Frame", nil, InterfaceOptionsFramePanelContainer)
+	-- CoA-compat: InterfaceOptionsFramePanelContainer is a global from the stock 3.3.5
+	-- Interface Options frame; on the CoA reworked FrameXML it can be nil at the time
+	-- AceGUI widgets are constructed. Fall back to UIParent so CreateFrame doesn't blow up.
+	local _parent = InterfaceOptionsFramePanelContainer or UIParent
+	local frame = CreateFrame("Frame", nil, _parent)
 	frame:Hide()
 
 	-- support functions for the Blizzard Interface Options
diff --git a/README.md b/README.md
index d5ee2ed..3f72549 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ Canonical [Ace3](https://www.wowace.com/projects/ace3) bundle for the CoA Guild
 
 Lifted from upstream [WoWUIDev/Ace3](https://github.com/WoWUIDev/Ace3) at commit
 [`52e5f2c`](https://github.com/WoWUIDev/Ace3/commit/52e5f2c7101b6edb02b48ea232bdda2df09d2960)
-(2026-05-17), with a single CoA-compat patch on top (see below). Every fork in the `Exiles`
+(2026-05-17), with a small stack of CoA-compat patches on top (see below). Every fork in the `Exiles`
 org should converge on this bundle so the runtime LibStub resolution is predictable and addons
 can't quietly regress when one of them is disabled.
 
@@ -13,6 +13,8 @@ can't quietly regress when one of them is disabled.
 | # | Issue | Fix |
 |---|-------|-----|
 | 1 | Upstream Ace3 calls `Texture:Set*Texture(<FileDataID>)` with numeric FileDataIDs in 42 places across `AceGUI-3.0/widgets/*` and `AceConfigDialog-3.0`. FileDataIDs are a retail-only API (post WoD/Legion). On the WoW 3.3.5-based CoA client, `SetTexture` only accepts string paths — passing a number silently fails and the engine renders a red placeholder. Symptom: solid-red squares where color swatches / checkboxes / window chrome should be. | Each FDID call was substituted with the string path that already lived in the trailing comment, e.g. `colorSwatch:SetTexture(130939)` → `colorSwatch:SetTexture("Interface\\ChatFrame\\ChatFrameColorSwatch")`. |
+| 2 | `AceGUI-3.0/widgets/AceGUIContainer-BlizOptionsGroup.lua` Constructor parents its frame to the global `InterfaceOptionsFramePanelContainer`. On the CoA reworked FrameXML that global is nil at AceGUI widget-construction time, and `CreateFrame("Frame", nil, nil)` is fine, but downstream code that calls `:SetPoint` against the parent / `:Show` it via the options tree relies on a real parent. Symptom: every addon that registers a Blizzard Interface Options panel via AceConfigDialog errors during load. | Guard at line 102: `local _parent = InterfaceOptionsFramePanelContainer or UIParent` and pass `_parent` to `CreateFrame`. Widget behaviour is unchanged on retail; on CoA the panel parents to `UIParent` so the rest of the widget works. |
+| 3 | `AceConfig-3.0/AceConfigDialog-3.0/AceConfigDialog-3.0.lua` `:AddToBlizOptions` uses the Dragonflight+ `Settings.*` API (`Settings.GetCategory`, `Settings.RegisterCanvasLayoutCategory`, `Settings.RegisterCanvasLayoutSubcategory`, `Settings.RegisterAddOnCategory`). The `Settings` table doesn't exist on the 3.3.5-based CoA client, so every AceConfig-driven options panel errors out the moment it's registered. | Wrap the whole `Settings.*` block in `if Settings and Settings.GetCategory then … else … end`. The `else` branch falls back to the WotLK-era `InterfaceOptions_AddCategory(group.frame)` after stamping the category name via `group:SetName(name or appName, parent)`. |
 
 ## Versions