diff --git a/Admin/isatest/settings/mac-poly-M2 b/Admin/isatest/settings/mac-poly-M2
--- a/Admin/isatest/settings/mac-poly-M2
+++ b/Admin/isatest/settings/mac-poly-M2
@@ -1,29 +1,29 @@
 # -*- shell-script -*- :mode=shellscript:
 
   POLYML_HOME="/home/polyml/polyml-5.4.0"
   ML_SYSTEM="polyml-5.4.0"
   ML_PLATFORM="x86-darwin"
   ML_HOME="$POLYML_HOME/$ML_PLATFORM"
-  ML_OPTIONS="--mutable 500 --immutable 500"
+  ML_OPTIONS="-H 500"
 
 
 ISABELLE_HOME_USER=~/isabelle-at-mac-poly-e
 
 # Where to look for isabelle tools (multiple dirs separated by ':').
 ISABELLE_TOOLS="$ISABELLE_HOME/lib/Tools"
 
 # Location for temporary files (should be on a local file system).
 ISABELLE_TMP_PREFIX="/tmp/isabelle-$USER"
 
 
 # Heap input locations. ML system identifier is included in lookup.
 ISABELLE_PATH="$ISABELLE_HOME_USER/heaps:$ISABELLE_HOME/heaps"
 
 # Heap output location. ML system identifier is appended automatically later on.
 ISABELLE_OUTPUT="$ISABELLE_HOME_USER/heaps"
 ISABELLE_BROWSER_INFO="$ISABELLE_HOME_USER/browser_info"
 
 ISABELLE_USEDIR_OPTIONS="-i false -d false -t true -M 2 -q 2"
 
 init_component "$HOME/contrib_devel/kodkodi"
 
diff --git a/Admin/isatest/settings/mac-poly-M4 b/Admin/isatest/settings/mac-poly-M4
--- a/Admin/isatest/settings/mac-poly-M4
+++ b/Admin/isatest/settings/mac-poly-M4
@@ -1,28 +1,28 @@
 # -*- shell-script -*- :mode=shellscript:
 
-  POLYML_HOME="/home/polyml/polyml-5.4.0"
-  ML_SYSTEM="polyml-5.4.0"
+  POLYML_HOME="/home/polyml/polyml-5.4.1"
+  ML_SYSTEM="polyml-5.4.1"
   ML_PLATFORM="x86-darwin"
   ML_HOME="$POLYML_HOME/$ML_PLATFORM"
-  ML_OPTIONS="--mutable 800 --immutable 800"
+  ML_OPTIONS="-H 1000"
 
 
 ISABELLE_HOME_USER=~/isabelle-mac-poly-M4
 
 # Where to look for isabelle tools (multiple dirs separated by ':').
 ISABELLE_TOOLS="$ISABELLE_HOME/lib/Tools"
 
 # Location for temporary files (should be on a local file system).
 ISABELLE_TMP_PREFIX="/tmp/isabelle-$USER"
 
 
 # Heap input locations. ML system identifier is included in lookup.
 ISABELLE_PATH="$ISABELLE_HOME_USER/heaps:$ISABELLE_HOME/heaps"
 
 # Heap output location. ML system identifier is appended automatically later on.
 ISABELLE_OUTPUT="$ISABELLE_HOME_USER/heaps"
 ISABELLE_BROWSER_INFO="$ISABELLE_HOME_USER/browser_info"
 
 ISABELLE_USEDIR_OPTIONS="-i false -d false -t true -M 4 -q 2"
 
 init_component "$HOME/contrib_devel/kodkodi"
diff --git a/Admin/isatest/settings/mac-poly-M8 b/Admin/isatest/settings/mac-poly-M8
--- a/Admin/isatest/settings/mac-poly-M8
+++ b/Admin/isatest/settings/mac-poly-M8
@@ -1,29 +1,29 @@
 # -*- shell-script -*- :mode=shellscript:
 
-  POLYML_HOME="/home/polyml/polyml-5.4.0"
-  ML_SYSTEM="polyml-5.4.0"
+  POLYML_HOME="/home/polyml/polyml-5.4.1"
+  ML_SYSTEM="polyml-5.4.1"
   ML_PLATFORM="x86-darwin"
   ML_HOME="$POLYML_HOME/$ML_PLATFORM"
-  ML_OPTIONS="--mutable 800 --immutable 800"
+  ML_OPTIONS="-H 1000"
 
 
 ISABELLE_HOME_USER=~/isabelle-mac-poly-M8
 
 # Where to look for isabelle tools (multiple dirs separated by ':').
 ISABELLE_TOOLS="$ISABELLE_HOME/lib/Tools"
 
 # Location for temporary files (should be on a local file system).
 ISABELLE_TMP_PREFIX="/tmp/isabelle-$USER"
 
 
 # Heap input locations. ML system identifier is included in lookup.
 ISABELLE_PATH="$ISABELLE_HOME_USER/heaps:$ISABELLE_HOME/heaps"
 
 # Heap output location. ML system identifier is appended automatically later on.
 ISABELLE_OUTPUT="$ISABELLE_HOME_USER/heaps"
 ISABELLE_BROWSER_INFO="$ISABELLE_HOME_USER/browser_info"
 
 ISABELLE_USEDIR_OPTIONS="-i false -d false -t true -M 8 -q 2"
 
 init_component "$HOME/contrib_devel/kodkodi"
 
diff --git a/Admin/isatest/settings/mac-poly64-M2 b/Admin/isatest/settings/mac-poly64-M2
--- a/Admin/isatest/settings/mac-poly64-M2
+++ b/Admin/isatest/settings/mac-poly64-M2
@@ -1,29 +1,29 @@
 # -*- shell-script -*- :mode=shellscript:
 
   POLYML_HOME="/home/polyml/polyml-5.4.0"
   ML_SYSTEM="polyml-5.4.0"
   ML_PLATFORM="x86_64-darwin"
   ML_HOME="$POLYML_HOME/$ML_PLATFORM"
-  ML_OPTIONS="--mutable 500 --immutable 500"
+  ML_OPTIONS="-H 1000"
 
 
 ISABELLE_HOME_USER=~/isabelle-at-mac-poly64-M2
 
 # Where to look for isabelle tools (multiple dirs separated by ':').
 ISABELLE_TOOLS="$ISABELLE_HOME/lib/Tools"
 
 # Location for temporary files (should be on a local file system).
 ISABELLE_TMP_PREFIX="/tmp/isabelle-$USER"
 
 
 # Heap input locations. ML system identifier is included in lookup.
 ISABELLE_PATH="$ISABELLE_HOME_USER/heaps:$ISABELLE_HOME/heaps"
 
 # Heap output location. ML system identifier is appended automatically later on.
 ISABELLE_OUTPUT="$ISABELLE_HOME_USER/heaps"
 ISABELLE_BROWSER_INFO="$ISABELLE_HOME_USER/browser_info"
 
 ISABELLE_USEDIR_OPTIONS="-i false -d false -t true -M 2 -q 2"
 
 init_component "$HOME/contrib_devel/kodkodi"