Add a 2nd row of image links in the home page

Hello, I am a beginner with WP. Mantra is the best choice of theme for my purpose. I tried adding a second row of images + links right below 4 placeholders available as part of the base theme. I am a beginner with php too. After spending a great deal of time in researching, I finally found that I can modify the settings.php (under admin folder) to add the additional image slides and by modifying theme_frontpage.php I can render the images onto the home page. I was successful with this first attempt. Then I had a requirement to add another row. I tried repeating the same steps. But it failed with the error “undefined index”. And I reverted back to the earlier working code, but that doesnt seem to work either.

Here is the changes I have made to the settings.php file.

Row no 549 (initially I had until 8 when it worked the first time, after the error, I am trying to make it work for just one more.
//SKP adding 5 to the array;
$items = array (“0″ ,”1”, “2” , “3” , “4” , “5” );

After row no 626
<!– SKP adding 5th column code begin–>
<div class=”slidebox”>
<h4 class=”slidetitle” > <?php _e(“5th Column”,”mantra”);?> </h4>
<div class=”slidercontent”>
<h5><?php _e(“Image”,”mantra”);?></h5>
<input name=”ma_options[mantra_columnimg5]” id=”mantra_columnimg5″ class=”slideimages” type=”text” value=”<?php echo esc_url($mantra_options[‘mantra_columnimg5’]); ?>” />
<span class=”description”><?php _e( ‘Select / Upload Image’, ‘mantra’ );?> </span>
<h5> <?php _e(“Title”,”mantra”);?> </h5>
<input id=’mantra_columntitle5′ name=’ma_options[mantra_columntitle5]’ size=’50’ type=’text’ value='<?php echo esc_attr( $mantra_options[‘mantra_columntitle5′] ) ?>’ />
<h5> <?php _e(“Text”,”mantra”);?> </h5>
<textarea id=’mantra_columntext5′ name=’ma_options[mantra_columntext5]’ rows=’3′ cols=’50’ type=’textarea’ ><?php echo esc_attr($mantra_options[‘mantra_columntext5′]) ?></textarea>
<h5> <?php _e(“Link”,”mantra”);?> </h5>
<input id=’mantra_columnlink5′ name=’ma_options[mantra_columnlink5]’ size=’50’ type=’text’ value='<?php echo esc_url( $mantra_options[‘mantra_columnlink5′] ) ?>’ />
</div>
</div>
<!– SKP adding 5th column code end –> >

It gives this error:

Notice: Undefined index: mantra_columnimg5 in C:\wamp\www\agroPedia\wp-content\themes\mantra\admin\settings.php on line 633

Could you please help me here? Thanks in advance..

-Senthil