diff --git a/kmk/handlers/layers.py b/kmk/handlers/layers.py
index 0e448dd..d436318 100644
--- a/kmk/handlers/layers.py
+++ b/kmk/handlers/layers.py
@@ -77,7 +77,7 @@ def tg_pressed(key, state, *args, **kwargs):
 
 def to_pressed(key, state, *args, **kwargs):
     """Activates layer and deactivates all other layers"""
-    state.active_layers = [key.meta.kc]
+    state.active_layers = [key.meta.layer]
     state.reversed_active_layers = list(reversed(state.active_layers))
 
     return state
diff --git a/kmk/internal_state.py b/kmk/internal_state.py
index b27454b..e552c01 100644
--- a/kmk/internal_state.py
+++ b/kmk/internal_state.py
@@ -67,8 +67,15 @@ class InternalState:
         else:
             timeout_key = ticks_ms() + after_ticks
 
+        while timeout_key in self.timeouts:
+            timeout_key += 1
+
         self.timeouts[timeout_key] = callback
-        return self
+        return timeout_key
+
+    def cancel_timeout(self, timeout_key):
+        if timeout_key in self.timeouts:
+            del self.timeouts[timeout_key]
 
     def process_timeouts(self):
         if not self.timeouts:
diff --git a/kmk/keys.py b/kmk/keys.py
index 0272acd..6ec36f0 100644
--- a/kmk/keys.py
+++ b/kmk/keys.py
@@ -60,7 +60,8 @@ class Key:
 
     def _on_press(self, state, coord_int, coord_raw):
         for fn in self._pre_press_handlers:
-            fn(self, state, KC, coord_int, coord_raw)
+            if not fn(self, state, KC, coord_int, coord_raw):
+                return None
 
         ret = self._handle_press(self, state, KC, coord_int, coord_raw)
 
@@ -71,7 +72,8 @@ class Key:
 
     def _on_release(self, state, coord_int, coord_raw):
         for fn in self._pre_release_handlers:
-            fn(self, state, KC, coord_int, coord_raw)
+            if not fn(self, state, KC, coord_int, coord_raw):
+                return None
 
         ret = self._handle_release(self, state, KC, coord_int, coord_raw)
 
@@ -110,8 +112,9 @@ class Key:
           provided for consistency with the internal handlers)
         - coord_raw (an X,Y tuple of the matrix coordinate - also likely not useful)
 
-        The return value of the provided callback is discarded. Exceptions are _not_
-        caught, and will likely crash KMK if not handled within your function.
+        If return value of the provided callback is evaluated to False, press
+        processing is cancelled. Exceptions are _not_ caught, and will likely
+        crash KMK if not handled within your function.
 
         These handlers are run in attachment order: handlers provided by earlier
         calls of this method will be executed before those provided by later calls.
@@ -156,8 +159,9 @@ class Key:
           provided for consistency with the internal handlers)
         - coord_raw (an X,Y tuple of the matrix coordinate - also likely not useful)
 
-        The return value of the provided callback is discarded. Exceptions are _not_
-        caught, and will likely crash KMK if not handled within your function.
+        If return value of the provided callback evaluates to False, the release
+        processing is cancelled. Exceptions are _not_ caught, and will likely crash
+        KMK if not handled within your function.
 
         These handlers are run in attachment order: handlers provided by earlier
         calls of this method will be executed before those provided by later calls.