Update docs with Phase 6 progress

CLAUDE.md: Update status to Phase 6 in progress, add new pitfalls
and key files discovered during verification.

PLAN.md: Mark Steps 1, 2, and 2b complete with results (50/50 CLSIDs,
13/13 DAT tests). Add DecalDat functional test as Step 2b.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -5,26 +5,35 @@ Open-source rebuild of **Decal**, the plugin framework for Asheron's Call.
 The original v2.9.8.3 is closed-source. This project produces a fully open-source
 drop-in replacement with identical COM interfaces and GUIDs for plugin compatibility.
 
-## Current Status: All 5 Phases Complete (Skeleton)
+## Current Status: Phase 6 — Verification In Progress
 
 The solution compiles with **25 C# projects, 0 errors**. Most COM server methods
 are **stubs** that need real implementations. See `docs/PLAN.md` for the full plan.
 
-### What's built:
+### What's built (Phases 1-5):
 - **Phase 1**: 14 decompiled .NET projects (Interop.*, Adapter, FileService, DecalUtil)
 - **Phase 2**: 10 native DLLs rewritten as C# COM servers with matching GUIDs
 - **Phase 3**: C++ shims — Inject.DLL (D3D9 hooking) + LauncherHook.DLL
 - **Phase 4**: DenAgent WinForms tray app replacing the MFC original
 - **Phase 5**: WiX installer + build script
 
-### What's next (Phase 6):
-Bottom-up verification — swap one original DLL at a time with our C# version,
-test against a running AC client, fix what breaks. See `docs/PLAN.md` "Phase 6".
+### Phase 6 Progress:
+- **DecalDat**: WORKING — 13/13 tests pass against real AC DAT files
+- **COM Registration**: PASS — 50/50 CLSIDs register and verify (0 GUID mismatches)
+- **Tools**: `tools/Test-ComRegistration.ps1` — regasm + registry verification
+- **Tests**: `Managed/Decal.DecalDat.Tests/` — console app smoke tests
+
+### What's next:
+- Smoke test DenAgent tray app
+- Integration test — swap one DLL at a time vs original Decal
+- Plugin compatibility (VTank, Mag-Tools)
 
 ## Key Files
 - `Managed/Decal.sln` — Main solution (25 projects)
 - `Managed/Directory.Build.props` — Shared build settings (net472, x86)
 - `Managed/Decal.Interop.*/` — COM interface contracts (the spec for everything)
+- `Managed/Decal.DecalDat.Tests/` — Smoke tests for DAT file I/O
+- `tools/Test-ComRegistration.ps1` — COM registration verification (regasm + registry check)
 - `Native/InjectModern/` — Inject.DLL C++ source (~530 lines)
 - `Native/LauncherHookModern/` — LauncherHook.DLL C++ source (~330 lines)
 - `Native/` — Old C++ source (reference for algorithms, NOT part of the build)
@@ -57,6 +66,11 @@ cmake --build build --config Release
 - LongValueKey enum: correct names are `keyStackCount`, `keyContainer`
 - tagPOINT defined in Interop.Inject, needed by Interop.Render → add ProjectReference
 - ICommandEvents delegates ambiguous between Interop.Controls and Interop.Inject → use `using` aliases
+- `GenerateAssemblyInfo=False` → use `[assembly: InternalsVisibleTo()]` attribute, not MSBuild items
+- `AppendTargetFrameworkToOutputPath=false` → DLLs at `bin\Release\`, NOT `bin\Release\net472\`
+- 32-bit regasm registers to `WOW6432Node` on 64-bit Windows — check both registry views
+- DAT file BTree root is at offset 0x160, NOT 0x148 (old C++ code was wrong)
+- BTree entries are 24 bytes (not 12) — see `dat-format.md` in memory
 
 ## Goal
 **Pixel-perfect drop-in replacement** for closed-source Decal v2.9.8.3,

docs/PLAN.md

@@ -92,32 +92,32 @@ All preserve original CLSIDs/GUIDs for plugin compatibility.
 
 ---
 
-## Phase 6: Verification & Implementation (NEXT)
+## Phase 6: Verification & Implementation (IN PROGRESS)
 
 Goal: **Pixel-perfect drop-in replacement** for the closed-source Decal v2.9.8.3.
 
 Strategy: **Bottom-up, one DLL at a time.** Replace one original DLL with our C#
 version while keeping all other original DLLs in place. Test. Move to the next.
 
-### Step 1: Build on Windows
+### Step 1: Build on Windows ✅ COMPLETE
 ```
-# C++ native projects (requires VS 2022 + Windows SDK)
-cd Native
-cmake -G "Visual Studio 17 2022" -A Win32 -B build
-cmake --build build --config Release
-
-# Managed solution
-dotnet build Managed\Decal.sln -c Release
+dotnet build Managed\Decal.sln -c Release   # 25 projects, 0 errors
 ```
 
-### Step 2: COM Registration Test
-Register all C# COM servers and verify GUIDs match originals:
-```
-regasm /codebase Managed\bin\Release\Decal.Core.dll
-regasm /codebase Managed\bin\Release\Decal.DecalDat.dll
-... (all 10 COM server DLLs)
-```
-Then verify in registry: `HKCR\CLSID\{GUID}\InprocServer32` points to our DLLs.
+### Step 2: COM Registration Test ✅ COMPLETE
+Automated script: `tools/Test-ComRegistration.ps1 -Build`
+- 10/10 DLLs register successfully with regasm /codebase
+- 50/50 CLSIDs verified in registry (WOW6432Node for 32-bit on 64-bit Windows)
+- 0 GUID mismatches vs original Decal .rgs files
+- 35 CLSIDs match original .rgs files exactly
+- 15 additional CLSIDs from decompiled interops (no .rgs source available)
+- 23 original CLSIDs not in scope (Inject module C++, internal action classes)
+
+### Step 2b: DecalDat Functional Test ✅ COMPLETE
+`Managed/Decal.DecalDat.Tests/` — 13/13 tests pass against real AC DAT files:
+- Opens portal.dat (884 MB, sector size 1024) and cell.dat (332 MB, sector size 256)
+- Reads 6 known file IDs from portal.dat (SpellTable, ComponentTable, etc.)
+- DatStream: Read, Restart, ReadBinary with Tell tracking
 
 ### Step 3: Smoke Test — DenAgent
 Run `Decal.DenAgent.exe` and verify: