docs(render): ledger — chunk 1 round 1 landed, three poses reproduce exactly; #458 doorway block admission; round 2 next

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/ISSUES.md

@@ -39,6 +39,28 @@ confirmed closed by the owner, 11 need a focused live gate, and 43 are safe to
 remain closed. See
 [`docs/research/2026-08-28-owner-closed-issue-validity-audit.md`](research/2026-08-28-owner-closed-issue-validity-audit.md).
 
+## #458 — Walk admits land block `a9c9` at holtburg-doorway-still that retail does not draw
+
+**Status:** OPEN — found 2026-09-03 by the S3 chunk 1 eight-kind transcript conformance (the gate's first real walk catch).
+**Severity:** MEDIUM (retail-order exactness; one far land cell drawn that retail skips — no known visible artifact)
+**Component:** `WalkLandscape.CheckBlocks` / `LandCellCheck` block-level visibility at a LOD-ring boundary
+
+**Symptom:** replaying `docs/research/2026-09-01-overhaul/oh-capture/holtburg-doorway-still.walk.log`
+frame 2 (camera cell `a9b4013f`) through `RetailFrameWalk`, the signature diverges at token 165:
+retail `…LC:a8c90001|SC:a8c90001|LC:95c60001…` vs acdream
+`…LC:a8c90001|SC:a8c90001|LC:a9c90001|SC:a9c90001|LC:95c60001…` — acdream admits the
+side-1 (ring ≥ 5) block `a9c9` through the interior root's exit views; retail's
+`LScape::draw_check_blocks` @0x00505f80 / `landcell_check` @0x005050a0 do not. The other
+three kit poses (terrace-edge, cathedral-arrival, foundry-deep) reproduce exactly.
+`WalkTraceConformanceTests.Oh_doorway_still_first_frame_diff` carries the row tagged
+`Status=KnownFailure` with the position documented.
+
+**Fix direction:** compare `WalkLandscape.CheckBlocks`' block edge-plane/CY test at that
+pose against the decomp (the per-view union, the block MinZ/MaxZ clip heights, the
+`mid_radius` bound) — a single block at the grid edge suggests the ring/bounds test or the
+exit-view edge planes, not the cell test. Resolve in the S3 review round or an S3 chunk 5;
+remove the KnownFailure trait in the same commit.
+
 ## #457 — Two App tests pass only in Release (IL-offset pins fail under Debug)
 
 **Status:** OPEN — found 2026-09-03 during the S3 chunk 3 re-review; pre-existing at `dffd7055` (before chunk 3), not a campaign regression.