diff --git a/classes/ComicPressBackend.inc b/classes/ComicPressBackend.inc
index 7ddd7ff..e494dc6 100644
--- a/classes/ComicPressBackend.inc
+++ b/classes/ComicPressBackend.inc
@@ -3,15 +3,19 @@
 class ComicPressBackend {
 	function _embed_image($size) {
 		$extras = array();
-		if (($dims = $this->dims($size)) !== false) {
-			$extras = array_merge($extras, $dims);
+    $dims = $this->dims($size);
+		if (!empty($dims)) {
+      if (is_array($dims)) {
+        $extras = array_merge($extras, $dims);
+      }
 		}
+    
 		foreach ($extras as $field => $value) {
-			$extras[] = "${field}=\"${value}\"";
+			$extras[] = "${field}=\"${value}\" ";
 			unset($extras[$field]);
 		}
 
-		$output = sprintf('<img src="%s" alt="%s" title="%s" %s />', $this->url(), $this->alt(), $this->title(), implode(" ", $extras));
+		$output = sprintf('<img src="%s" alt="%s" title="%s" %s/>', $this->url(), $this->alt(), $this->title(), implode("", $extras));
 		return apply_filters('comicpress_embed_image', $output, $this);
 	}
 }
\ No newline at end of file
diff --git a/classes/ComicPressNavigation.inc b/classes/ComicPressNavigation.inc
index 31288a9..a025259 100644
--- a/classes/ComicPressNavigation.inc
+++ b/classes/ComicPressNavigation.inc
@@ -4,10 +4,12 @@ require_once('ComicPressStoryline.inc');
 require_once('ComicPressDBInterface.inc');
 
 class ComicPressNavigation {
+  // @codeCoverageIgnoreStart
   function init($storyline) {
     $this->_storyline = $storyline;
     $this->_dbi       = ComicPressDBInterface::get_instance();
   }
+  // @codeCoverageIgnoreEnd
 
   function get_post_nav($post) {
     $nav = array();
@@ -61,6 +63,7 @@ class ComicPressNavigation {
 				return $nav;
 			}
 		}
+    return false;
   }
 }
 
diff --git a/test/ComicPressBackendTest.php b/test/ComicPressBackendTest.php
new file mode 100644
index 0000000..b9f341e
--- /dev/null
+++ b/test/ComicPressBackendTest.php
@@ -0,0 +1,45 @@
+<?php
+
+require_once('PHPUnit/Framework.php');
+require_once('MockPress/mockpress.php');
+require_once('ComicPressBackend.inc');
+
+class ComicPressBackendTest extends PHPUnit_Framework_TestCase {
+  function providerTestEmbedImage() {
+    return array(
+      array(
+        false, array(
+          '#^<img src="http://comic" alt="alt" title="title" />$#'
+        )
+      ),
+      array(
+        array(), array(
+          '#^<img src="http://comic" alt="alt" title="title" />$#'
+        )
+      ),
+      array(
+        array('width' => 320, 'height' => 240), array(
+          '#^<img src="http://comic" alt="alt" title="title" width="320" height="240" />$#'
+        )
+      ),
+    );
+  }
+
+  /**
+   * @dataProvider providerTestEmbedImage
+   */
+  function testEmbedImage($dims_result, $expected_result_patterns) {
+    $backend = $this->getMock('ComicPressBackend', array('dims', 'url', 'alt', 'title'));
+
+    $backend->expects($this->once())->method('dims')->with('comic')->will($this->returnValue($dims_result));
+    $backend->expects($this->once())->method('url')->will($this->returnValue('http://comic'));
+    $backend->expects($this->once())->method('alt')->will($this->returnValue('alt'));
+    $backend->expects($this->once())->method('title')->will($this->returnValue('title'));
+
+    $result = $backend->_embed_image('comic');
+
+    foreach ($expected_result_patterns as $pattern) {
+      $this->assertTrue(preg_match($pattern, $result) > 0);
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/ComicPressNavigationTest.php b/test/ComicPressNavigationTest.php
index 7579fe1..24da147 100644
--- a/test/ComicPressNavigationTest.php
+++ b/test/ComicPressNavigationTest.php
@@ -13,6 +13,14 @@ class ComicPressNavigationTest extends PHPUnit_Framework_TestCase {
     $this->nav = new ComicPressNavigation();
   }
 
+  function testGetPostNavNotAPost() {
+    $this->assertTrue($this->nav->get_post_nav(false) === false);
+  }
+
+  function testGetPostNavFromCache() {
+    $this->markTestIncomplete();
+  }
+
   function testGetPostNav() {
     $dbi = $this->getMock('ComicPressDBInterface', array('get_previous_comic', 'get_next_comic', 'get_first_comic', 'get_last_comic'));
     $storyline = new ComicPressStoryline();