diff --git a/build.sh b/build.sh
index 2ee3a97498..039c1b3641 100755
--- a/build.sh
+++ b/build.sh
@@ -14,6 +14,16 @@ LATEST_CKAN_META="https://github.com/KSP-CKAN/CKAN-meta/archive/master.tar.gz"
 # Third party utilities.
 JQ_PATH="jq"
 
+# Return codes.
+EXIT_OK=0
+
+# Allow us to specify a commit id as the first argument
+if [ -n "$1" ]
+then
+    echo "Using CLI argument of $1"
+    ghprbActualCommit=$1
+fi
+    
 # ------------------------------------------------
 # Function for creating dummy KSP directories to
 # test on. Takes version as an argument.
@@ -104,18 +114,71 @@ create_dummy_ksp () {
     ln -s downloads_cache dummy_ksp/CKAN/downloads
 }
 
+# ------------------------------------------------
+# Function for injecting metadata into a tar.gz
+# archive. Assummes metadata.tar.gz to be present.
+# ------------------------------------------------
+inject_metadata () {
+    # TODO: Arrays + Bash Functions aren't fun. This needs
+    # Improvement but appears to work. The variables are
+    # available to the called functions.
+
+    # Check input, requires at least 1 argument.
+    if [ $# -ne 1 ]
+    then
+        echo "Nothing to inject."
+        cp metadata.tar.gz master.tar.gz
+        return 0
+    fi
+   
+    # Extract the metadata into a new folder.
+    rm -rf CKAN-meta-master
+    tar -xzf metadata.tar.gz
+    
+    # Copy in the files to inject.
+    # TODO: Unsure why this suddenly needs [*] declaration
+    # but it does work
+    for f in ${OTHER_FILES[*]}
+    do
+        echo "Injecting $f"
+        cp $f CKAN-meta-master
+    done
+    
+    # Recompress the archive.
+    rm -f master.tar.gz
+    tar -czf master.tar.gz CKAN-meta-master
+}
+
+# ------------------------------------------------
+# Main entry point.
+# ------------------------------------------------
+
 # Find the changes to test.
 echo "Finding changes to test..."
 
-if [ -n $ghprbActualCommit ]
+if [ -n "$ghprbActualCommit" ]
 then
-    echo Commit hash: $ghprbActualCommit
-    echo Changes in this commit:
+    echo "Commit hash: $ghprbActualCommit"
     export COMMIT_CHANGES="`git diff --diff-filter=AM --name-only --stat origin/master`"
-    echo $COMMIT_CHANGES
 else
-    echo "No commit ID to test"
-    exit 1
+    echo "No commit provided, skipping further tests."
+    exit $EXIT_OK
+fi
+
+# Make sure we start from a clean slate.
+if [ -d "downloads_cache/" ]
+then
+    rm -rf downloads_cache
+fi
+
+if [ -e "master.tar.gz" ]
+then
+    rm -f master.tar.gz
+fi
+
+if [ -e "metadata.tar.gz" ]
+then
+    rm -f metadata.tar.gz
 fi
 
 # CKAN Validation files
@@ -125,7 +188,7 @@ chmod a+x ckan-validate.py
 
 # fetch latest ckan.exe
 echo "Fetching latest ckan.exe"
-wget --quiet $LATEST_CKAN_URL -O ckan.exe
+#wget --quiet $LATEST_CKAN_URL -O ckan.exe
 
 # Fetch the latest metadata.
 echo "Fetching latest metadata"
@@ -138,22 +201,22 @@ then
     mkdir downloads_cache
 fi
 
-for f in $COMMIT_CHANGES
+for ckan in $COMMIT_CHANGES
 do
     # set -e doesn't apply inside an if block CKAN#1273
-    if [ "$f" = "build.sh" ]; then
+    if [ "$ckan" = "build.sh" ]; then
       echo "Lets try not to validate our build script with CKAN"
       continue
     fi
     
-    ./ckan-validate.py $f
+    ./ckan-validate.py $ckan
     echo ----------------------------------------------
-    cat $f | python -m json.tool
+    cat $ckan | python -m json.tool
     echo ----------------------------------------------
 
     # Extract identifier and KSP version.
-    CURRENT_IDENTIFIER=$($JQ_PATH '.identifier' $f)
-    CURRENT_KSP_VERSION=$($JQ_PATH 'if .ksp_version then .ksp_version else .ksp_version_min end' $f)
+    CURRENT_IDENTIFIER=$($JQ_PATH '.identifier' $ckan)
+    CURRENT_KSP_VERSION=$($JQ_PATH 'if .ksp_version then .ksp_version else .ksp_version_min end' $ckan)
     
     # Strip "'s.
     CURRENT_IDENTIFIER=${CURRENT_IDENTIFIER//'"'}
@@ -162,14 +225,29 @@ do
     echo "Extracted $CURRENT_IDENTIFIER as identifier."
     echo "Extracted $CURRENT_KSP_VERSION as KSP version."
     
+    # Get a list of all the OTHER files.
+    OTHER_FILES=()
+   
+    for o in $COMMIT_CHANGES
+    do
+        if [ "$ckan" != "$o" ] && [ "$ckan" != "build.sh" ]
+        then
+            OTHER_FILES+=($o)
+        fi
+    done
+    echo "Other files: ${OTHER_FILES[*]}"
+
+    # Inject into metadata.
+    inject_metadata $OTHER_FILES
+    
     # Create a dummy KSP install.
     create_dummy_ksp $CURRENT_KSP_VERSION $ghprbActualCommit
 
     echo "Running ckan update"
     mono ckan.exe update
 
-    echo Running ckan install -c $f
-    mono --debug ckan.exe install -c $f --headless
+    echo Running ckan install -c $ckan
+    mono --debug ckan.exe install -c $ckan --headless
 
     # Show all installed mods.
     echo "Installed mods:"