diff --git a/CHANGELOG.md b/CHANGELOG.md
index 19ac47f..5301f86 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,38 @@ Tags below the 0.5 line were placed retroactively on 2026-04-19.
 The corresponding commit messages carry the canonical release
 notes; this file is a quick index.
 
+## 0.5.2 -- 2026-04-19 (FTS-conformance fixes from NR hpt-compare suite)
+
+Two consumer-surfaced interop bugs in `mb.kludge`, both caught by
+NetReader's hpt-vs-nr byte-diff harness.  Real-world impact:
+previous `BuildKludgePrefix` output failed to round-trip through
+HPT / fmail / NR for FLAGS kludges, and previous `SplitKludgeBlob`
+leaked the FTS-0004 AREA: envelope into on-disk bodies.
+
+- **`BuildKludgePrefix` FLAGS emission** used a colon separator
+  (`^AFLAGS: DIR`), but FTS-4001 §4 specifies a space (`^AFLAGS DIR`)
+  and every downstream parser (NR's ParseKludges, HPT's getFlags,
+  fmail's getKludge) expects no colon.  Symptom: FLAGS DIR / IMM
+  routing silently fell through to normal routing because consumers
+  didn't recognise the kludge at all.  Fix: one-line drop of the
+  colon from the emit template.  `MSGID:` / `REPLY:` / `PID:` /
+  `CHRS:` / `TZUTC:` keep their colons per their respective specs.
+  Commit: `cd2cc90`.
+- **`ParseKludgeLine` AREA: recognition.**  FTS-0004 puts
+  `AREA:<tag>` at the head of a packet-message body with no SOH
+  prefix, same shape as the `SEEN-BY:` / `PATH:` trailing control
+  lines the parser already handled.  Without AREA: in the trail-
+  control list, `SplitKludgeBlob` left the envelope in PlainBody,
+  so msgbase writers stored `AREA:BINECHO` as the first ~12 bytes
+  of the on-disk message body.  Symptom (NR): UUE decode output
+  inflated by the envelope length per section.  Fix: add `AREA:`
+  to the isTrailControl list and dispatch `'area':` into
+  `A.SetValue('area', ...)` -- same attribute slot 0.5.0 already
+  populates from `MessageBaseOpen`'s area-tag argument on reads.
+  Commit: `ee0f1ca`.
+
+Thanks to NR for catching both via the hpt-compare harness.
+
 ## 0.5.1 -- 2026-04-19 (security-hardening round)
 
 Retroactive tagging discipline established.  Before this release,
diff --git a/README.md b/README.md
index dce8fe7..1df7f89 100644
--- a/README.md
+++ b/README.md
@@ -114,9 +114,9 @@ Unit-name convention follows the Fimail style: `ma.<category>.<name>.pas`
 
 Early development. APIs may move until 1.0.
 
-**Current: 0.5.1** — see [`CHANGELOG.md`](CHANGELOG.md) for the full
+**Current: 0.5.2** — see [`CHANGELOG.md`](CHANGELOG.md) for the full
 release history.  Downstream consumers should pin by tag
-(`v0.5.1`), not commit hash.
+(`v0.5.2`), not commit hash.
 
 **0.2 is a breaking change vs 0.1.** `TUniMessage` lost its 13 named
 fields (WhoFrom/WhoTo/Subject/MsgNum/Attr/etc.) in favour of a strict
diff --git a/src/mb.version.pas b/src/mb.version.pas
index 4bf8faf..ec2d03b 100644
--- a/src/mb.version.pas
+++ b/src/mb.version.pas
@@ -17,8 +17,8 @@ interface
 const
   MB_VERSION_MAJOR = 0;
   MB_VERSION_MINOR = 5;
-  MB_VERSION_PATCH = 1;
-  MB_VERSION       = '0.5.1';
+  MB_VERSION_PATCH = 2;
+  MB_VERSION       = '0.5.2';
 
 implementation