diff --git a/init.lua b/init.lua
index 87e38d7..b104881 100644
--- a/init.lua
+++ b/init.lua
@@ -40,9 +40,11 @@ local ci_assets_traced = false
 local WALK_ANIMS = {"walk_fwd_lower", "walk_back_lower", "walk_left_lower", "walk_right_lower"}
 
 -- Signed angle between two 2D vectors (in degrees, range [-180, 180]).
--- Returns the signed angle from v1 to v2, positive = counter-clockwise (left).
+-- Sporel uses Y-down screen-coords. Substrate's math assumes Y-up; the cross
+-- component is flipped so "positive num = move-direction is CCW from body-fwd
+-- in screen-coords" matches substrate's "positive num = walk_left sector".
 local function signed_angle_2d(v1x, v1y, v2x, v2y)
-    local cross = v1x * v2y - v1y * v2x
+    local cross = v1y * v2x - v1x * v2y   -- Y-down flip
     local dot   = v1x * v2x + v1y * v2y
     return math.deg(math.atan(cross, dot))
 end
diff --git a/rigs/humanoid.rig.json b/rigs/humanoid.rig.json
index ce1c8e1..e3ecbd0 100644
--- a/rigs/humanoid.rig.json
+++ b/rigs/humanoid.rig.json
@@ -5,7 +5,7 @@
     { "id": "root",          "parent": null,              "rest": {"x":   0, "y":   0, "rot": 0},                   "z_order": -1 },
     { "id": "lower_control", "parent": "root",            "rest": {"x":   0, "y":   0, "rot": 0},                   "virtual": true },
     { "id": "body",          "parent": "root",            "rest": {"x":   0, "y":   0, "rot": 0},                   "z_order":  2, "texture": "body_001", "look_at": "soft", "look_at_slerp": 6 },
-    { "id": "head",          "parent": "body",            "rest": {"x":   0, "y":  -3, "rot": 0, "rot_min": -60, "rot_max": 60}, "z_order":  6, "texture": "head_001", "look_at": "aim", "sprite_rot": -90 },
+    { "id": "head",          "parent": "body",            "rest": {"x":   0, "y":  -3, "rot": 0, "rot_min": -60, "rot_max": 60}, "z_order":  6, "texture": "head_001", "look_at": "aim" },
     { "id": "shoulders",     "parent": "body",            "rest": {"x":   0, "y":   0, "rot": 0},                   "z_order":  5, "texture": "shoulder_001" },
     { "id": "upper_arm_l",   "parent": "shoulders",       "rest": {"x": -19, "y":  -3, "rot": 0, "scl": [-1,  1]}, "z_order":  3, "texture": "upper_arm_001" },
     { "id": "upper_arm_r",   "parent": "shoulders",       "rest": {"x":  20, "y":  -4, "rot": 0},                   "z_order":  3, "texture": "upper_arm_001" },