diff --git a/phraskell.cabal b/phraskell.cabal
--- a/phraskell.cabal
+++ b/phraskell.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                phraskell
-version:             0.1.1
+version:             0.1.2
 synopsis:            A fractal viewer.
 description:         A fractal viewer with some cool features like changing colorscheme, screenshot, buddhabrot, and so on.
 homepage:            https://github.com/skypers/phraskell
@@ -21,7 +21,7 @@
 source-repository this
   type:                git
   location:            git://github.com/skypers/phraskell.git
-  tag:                 0.1.1
+  tag:                 0.1.2
 
 executable phraskell
   main-is:             Phraskell.hs
diff --git a/src/UI.hs b/src/UI.hs
--- a/src/UI.hs
+++ b/src/UI.hs
@@ -16,9 +16,10 @@
     KeyUp k -> case symKey k of
       SDLK_ESCAPE    -> quit
       SDLK_SPACE     -> alter $ \a -> let vg = appVisibleGUI a in return a { appVisibleGUI = not vg }
+      SDLK_RETURN    -> alter onFractalFrameUpdate
       SDLK_MINUS     -> alter $ (\a -> let v    = appViewer a
                                            maxi = viewerMaxIter v
-                                       in return a { appViewer = v { viewerMaxIter = maxi-50 } })
+                                       in return a { appViewer = v { viewerMaxIter = max 0 $ maxi-50 } })
       SDLK_PLUS      -> alter $ (\a -> let v    = appViewer a
                                            maxi = viewerMaxIter v
                                        in return a { appViewer = v { viewerMaxIter = maxi+50 } })
@@ -27,7 +28,7 @@
       SDLK_LEFTPAREN  -> do
         let v  = appViewer app
             zf = viewerZoomf v
-            na = app { appViewer = v { viewerZoomf = zf-0.1 } }
+            na = app { appViewer = v { viewerZoomf = max 0.1 $ zf-0.1 } }
         newGUI <- updateGUIZoomArea (appGUI na) (appViewer na)
         loopback $ na { appGUI = newGUI }
       SDLK_RIGHTPAREN  -> do