I went to https://wordpress.org/plugins/powerpress/advanced/ and downloaded PowerPress.9.8.1 and did a manual install (ftp the files to the /wp-content/plugins/powerpress folder on my site). I deactivated PowerPress first, uploaded the roll-back, then reactivated. Everything works for now.
You can remove the “Search for:” text by editing (WP version 2.8) wp-includes\general-template.php
Line 125
<div><label class="screen-reader-text" for="s">' . __('<!--Search for:-->') . '</label>
I commented it out (as seen above) so it wouldn’t show. Hope that helps.