diff --git a/Core.lua b/Core.lua
index a2118e3..fff36a1 100644
--- a/Core.lua
+++ b/Core.lua
@@ -12,14 +12,11 @@ AltSystem.State = {
 -- Initialization on ADDON_LOADED
 local frame = CreateFrame("Frame")
 frame:RegisterEvent("ADDON_LOADED")
-frame:RegisterEvent("PLAYER_LOGIN")
 
 frame:SetScript("OnEvent", function(self, event, arg1)
     if event == "ADDON_LOADED" and arg1 == "AltSystem" then
         AltSystem:Init()
-    elseif event == "PLAYER_LOGIN" then
-        AltSystem:RegisterTRP3Button()
-        AltSystem:RegisterMinimapButton()
+        AltSystem:RegisterTRP3Module()
     end
 end)
 
@@ -43,55 +40,44 @@ function AltSystem:ToggleWindow()
     end
 end
 
--- TRP3 toolbar button registration
+-- Register as a TRP3 module so our onStart runs in the correct lifecycle phase
+-- (after the toolbar module is initialized, but before WORKFLOW_ON_FINISH locks it)
+function AltSystem:RegisterTRP3Module()
+    if not TRP3_API or not TRP3_API.module then
+        return
+    end
+
+    local MODULE_STRUCTURE = {
+        ["name"] = "AltSystem",
+        ["description"] = "AltSystem rolling window toolbar button",
+        ["version"] = 1.000,
+        ["id"] = "altsystem_module",
+        ["onStart"] = function()
+            AltSystem:RegisterTRP3Button()
+        end,
+        ["minVersion"] = 3,
+        ["requiredDeps"] = {
+            {"trp3_tool_bar", 1},
+        },
+    }
+
+    TRP3_API.module.registerModule(MODULE_STRUCTURE)
+end
+
+-- TRP3 toolbar button registration (called from the TRP3 module onStart)
 function AltSystem:RegisterTRP3Button()
     if TRP3_API and TRP3_API.toolbar then
         local toolbarButton = {
             id = "altsystem_toolbar_btn",
-            icon = "Interface\\Icons\\INV_Misc_Dice_02",
+            icon = "Interface\\Icons\\INV_Misc_Dice_01",
             tooltip = "AltSystem",
             tooltipSub = "Open the AltSystem rolling window",
             onClick = function()
                 AltSystem:ToggleWindow()
             end,
+            visible = 1,
         }
         TRP3_API.toolbar.toolbarAddButton(toolbarButton)
     end
 end
 
--- Minimap button using LibDBIcon (lightweight fallback if not available)
-function AltSystem:RegisterMinimapButton()
-    -- Simple minimap button without external libraries
-    local minimapButton = CreateFrame("Button", "AltSystemMinimapButton", Minimap)
-    minimapButton:SetSize(32, 32)
-    minimapButton:SetFrameStrata("MEDIUM")
-    minimapButton:SetFrameLevel(8)
-    minimapButton:SetPoint("TOPLEFT", Minimap, "TOPLEFT", 2, -2)
-
-    local icon = minimapButton:CreateTexture(nil, "ARTWORK")
-    icon:SetTexture("Interface\\Icons\\INV_Misc_Dice_02")
-    icon:SetSize(20, 20)
-    icon:SetPoint("CENTER")
-
-    local border = minimapButton:CreateTexture(nil, "OVERLAY")
-    border:SetTexture("Interface\\Minimap\\MiniMap-TrackingBorder")
-    border:SetSize(54, 54)
-    border:SetPoint("TOPLEFT", -2, 2)
-
-    minimapButton:SetHighlightTexture("Interface\\Minimap\\UI-Minimap-ZoomButton-Highlight")
-
-    minimapButton:SetScript("OnClick", function()
-        AltSystem:ToggleWindow()
-    end)
-
-    minimapButton:SetScript("OnEnter", function(self)
-        GameTooltip:SetOwner(self, "ANCHOR_LEFT")
-        GameTooltip:AddLine("AltSystem")
-        GameTooltip:AddLine("Click to toggle the rolling window", 1, 1, 1)
-        GameTooltip:Show()
-    end)
-
-    minimapButton:SetScript("OnLeave", function()
-        GameTooltip:Hide()
-    end)
-end