diff --git a/sequencer/sequencer.sh b/sequencer/sequencer.sh
index 207214d..7e7a3de 100755
--- a/sequencer/sequencer.sh
+++ b/sequencer/sequencer.sh
@@ -54,27 +54,56 @@ helpSequencer() {
 helpApi() {
   echo "sequencer.sh build-in functions"
   echo
-  echo " echoerr <...>"
-  echo "    echo output to stderr"
-  echo "    <...> - all parameter are forwarded to echo"
+  echo " exe [COMMANDLINE]"
+  echo "    Execute command line without pipes or redirects (>,<,|)."
+  echo "    Supporting: dry-run (-d): only print command without execution" 
+  echo "                verbose (-v): print command before execution"
   echo
-  echo " endCheckEmpty <Variable Name> [Description]"
-  echo "    exit 666 if variable is empty"
-  echo "    <Variable Name> - Name used within eval"
-  echo "    [Description]   - Additional text for error output"
+  echo " exep \"[COMMANDLINE]\""
+  echo "    See exe, but support for pipes or redirects."
+  echo "    Since the command line is given as string all apostrophes need to be esacped."
   echo
-  echo " saveReturn [Error Code]"
-  echo "    Save error code if it is != 0 for later use with endReturn"
-  echo
-  echo " endReturn [-f] [Message]"
-  echo "    Notifys user that there was an error (previously saved by saveReturn)"
-  echo "    and asks to continue or end sequence. Always exits with saved error code."
-  echo "    -f : force exit with the last saved error code  without user input"
+  echo " addConf <OPTIONS> <CONFIGTEXT> <CONFIGFILE>"
+  echo "    Trying to write or append to a file."
+  echo "    If the CONFIGFILE exists, a backup (name_%Y%m%d-%H%M%S.bck) is saved at the same location."
+  echo "    If -s fails or -m, \"$(realpath "$MISSING_CONF")\" is created with the conflicts"
+  echo "    to be resolved by the user."
+  echo "      <OPTIONS>"
+  echo "        -c : create a new file"
+  echo "        -a : append to existing file"
+  echo "        -s : skip if CONFIGFILE exists (no backup and entry in missing conf)"
+  echo "        -m : only add content to missing conf and warn user"
+  echo "      <CONFIGTEXT>"
+  echo "        Text to be created or added to <CONFIGFILE>"
+  echo "      <CONFIGFILE>"
+  echo "        Target file to be created or modified."
   echo
   echo " step <Step number or alias>"
   echo "    Executes a single step also by alias. Useful if step numbers get reorganized."
   echo "    dry-run is not applied in this function! The executed step is responsible."
   echo
+  echo " echoerr [...]"
+  echo "    echo to stderr"
+  echo "      [...] : all parameter are forwarded to echo"
+  echo
+  echo " endCheckEmpty <VARIABLENAME> [DESCRIPTION]"
+  echo "    exit 666 if variable is empty"
+  echo "      <VARIABLENAME> : Name used within eval"
+  echo "      [DESCRIPTION]  : Additional text for error output"
+  echo
+  echo " saveReturn [ERRORCODE]"
+  echo "    Save ERRORCODE if it is != 0 for later use with endReturn"
+  echo
+  echo " getReturn"
+  echo "    Return last saved error code"
+  echo
+  echo " endReturn [-f] [-o ERRORCODE] [MESSAGE]"
+  echo "    Notifys user that there was an error (previously saved by saveReturn,"
+  echo "    or -o [ERRORCODE]) and asks to continue or end the sequence."
+  echo "    Always exits with evaluated error code."
+  echo "      -f : force exit without user input, if error code is not 0"
+  echo "      -o : override stored error code and check ERRORCODE"
+  echo
 }
 
 # Echo to stderr
@@ -116,19 +145,31 @@ getReturn() {
   return $ERNO
 }
 
-# endReturn [-f] [MESSAGE]
+# endReturn [-f] [-o ERRORCODE] [MESSAGE]
 #      -f : force exit with $ERNO without user input
+#      -o : override and check given error code
 # MESSAGE : Custom error message
 #
 endReturn() {
   local forceExit=0
+  local errorCode=$ERNO
   local endMessage=""
 
   for arg in "$@" ; do
     case "$1" in
       -f)
         forceExit=1
-        skipStep=0
+        shift
+        ;;
+      -o)
+        shift
+        local rex='^[-]*[0-9]+$'
+        # Check if string is a number or alias 
+        if [[ "$1" =~ $rex ]] ; then
+          errorCode=$1
+        else
+          echoerr " [W] Ignoring invalid error code: $1"
+        fi
         shift
         ;;
       "")
@@ -141,32 +182,34 @@ endReturn() {
     esac
   done
 
-  if [[ ( $ERNO -ne 0 && $QUIET -ne 0 ) || ( $ERNO -ne 0 && $forceExit -ne 0 ) ]] ; then
+  if [[ ( $errorCode -ne 0 && $QUIET -ne 0 ) || ( $errorCode -ne 0 && $forceExit -ne 0 ) ]] ; then
     echo
     if [ "$endMessage" != "" ]; then
       echoerr -e " [E] $endMessage\n     Sequence stopped"
     else
-      echoerr -e " [E] Return value $ERNO detected.\n     Sequence stopped"
+      echoerr -e " [E] Return value $errorCode detected.\n     Sequence stopped"
     fi
-    exit $ERNO
+    exit $errorCode
   fi
-  if [ $ERNO -ne 0 ] ; then
+  if [ $errorCode -ne 0 ] ; then
     echo
     if [ "$endMessage" != "" ]; then
       echoerr -e " [W] $endMessage"
     else
-      echoerr " [W] Return value $ERNO detected."
+      echoerr " [W] Return value $errorCode detected."
     fi
     read -p "End sequence: [y]/n? " answer
     case $answer in
       [nN])
+        # reset saved error code if user chooses to continue
+        ERNO=0
         echo
         echo " [I] Continuing sequence..."
         ;;
       *)
         echo
         echoerr " [E] Sequence stopped"
-        exit $ERNO; 
+        exit $errorCode; 
         ;;
     esac
   fi
@@ -192,7 +235,7 @@ addConf() {
       confMode="-m"
       ;;
     *) # default
-      echo "Parameter 1 (-a|-c|-m|-s) missing for addConf()"
+      echoerr " [E] Parameter 1 (-a|-c|-m|-s) missing for addConf()"
       exit 0;
       ;;
   esac
@@ -231,14 +274,15 @@ addConf() {
         else
           echo "$2" >> "$3"
         fi
-        echo -e "ok \n [W] Existing config saved to ${addConfBackup}"
+        echo -e "ok \n [I] Existing config saved to ${addConfBackup}"
         return 0
       else
-        echo "nok (backup exists)"
+        echo "nok"
+        echoerr " [W] backup exists"
       fi
     fi
   else
-    echo "nok (no change requested)"
+    echo -e "ok \n [I] no change requested"
   fi
 
   # add configuration to missingConf file
@@ -270,7 +314,7 @@ execute() {
   # check if step function exists
   declare -F step_$1 &>>/dev/null || NOTFOUND=1
   if [ $NOTFOUND -eq 1 ] && [ $NOREPORT -ne 1 ] ; then
-    echo "Step $1 not found" 
+    echoerr " [E] Step $1 not found" 
     exit 1;
   fi