ok the auto driver works but needs work

src/core/FixedStep.lua

@@ -12,8 +12,15 @@ function FixedStep:init(callback)
   self.callback = callback
 end
 
+-- The anti-spiral clamp doubles as a steps-per-frame ceiling (0.25s = 15
+-- steps), which silently throttled the high fast-forward levels: at 100X
+-- a 60fps frame wants ~100 steps. Game:update raises this to fit the
+-- current speed target; a stall still cannot snowball past one frame's
+-- intended budget.
+FixedStep.maxAccum = MAX_ACCUM
+
 function FixedStep:update(dt)
-  self.accum = math.min(self.accum + dt, MAX_ACCUM)
+  self.accum = math.min(self.accum + dt, self.maxAccum or MAX_ACCUM)
   while self.accum >= self.STEP do
     self.accum = self.accum - self.STEP
     self.callback(self.STEP)

src/core/Game.lua

@@ -170,7 +170,11 @@ function Game:update(dt)
   -- deferred A and edge pulses land in Input's press queue for this step.
   TouchInput:update(dt)
   -- Fast-forward scales only the logic clock (see src/core/GameSpeed.lua).
-  FixedStep:update(dt * self:logicSpeed())
+  -- Give the accumulator room for one full frame at the current speed,
+  -- or the anti-spiral clamp quietly caps every level above ~15X.
+  local speed = self:logicSpeed()
+  FixedStep.maxAccum = math.max(0.25, speed * FixedStep.STEP * 1.5)
+  FixedStep:update(dt * speed)
   -- Audio runs off real time at a fixed 60Hz regardless of game speed or
   -- display refresh, so fades and chip synthesis keep their intended tempo
   -- whether we are at 1X, 10X, or running with vsync disabled.

src/core/GameSpeed.lua

@@ -18,7 +18,7 @@ local GameSpeed = {}
 -- attempt is long enough that the iteration loop, not the engine, is the
 -- bottleneck. Vsync caps how much a real frame can do, so past 10X the
 -- multiplier is increasingly a ceiling rather than a rate.
-GameSpeed.LEVELS = { 1, 2, 4, 10, 20, 30, 50, 75 }
+GameSpeed.LEVELS = { 1, 2, 4, 10, 20, 30, 50, 75, 100,500 }
 GameSpeed.DEFAULT = 1
 
 function GameSpeed.levelLabel(v)