Java Script is acting suddenly unexpected

I have used successfully over long time the below JS function in my theme options page. It does save the WP Theme Options by JS and puts a message on my screen once saved.

Suddenly, if I change the timeout settings (value) the message does either not show at all, or does show but does not hide anymore.

This is my JS:

<!--Include AJAX save message + styles-->
   <div id="saveResult"></div>
<script type="text/javascript">
jQuery(document).ready(function() {
jQuery('#myOptionsForm').submit(function() { 
  jQuery(this).ajaxSubmit({
     success: function(){
        jQuery('#saveResult').html("<div id='saveMessage'class='successModal'></div>");
        jQuery('#saveMessage').append("<p><?php echo htmlentities(__('Settings Saved Successfully','wp'),ENT_QUOTES); ?></p>").show();
     }, 
     timeout: 5000
  }); 
  setTimeout("jQuery('#saveMessage').hide('slow');", 5000);
  return false; 
});
});
</script>

This is the according CSS:

.successModal {
display: block;
position: fixed;
top: 35%;
left: 20%;
border-radius: 50% !important;;
width: 123px;
height: 153px;
padding: 5px 20px;
background-image: url("Smile-success.png");
z-index:1002;
overflow: auto;
background-position: center center;
background-repeat: no-repeat;
-moz-border-radius: 15px; 
-webkit-border-radius: 15px;
-moz-box-shadow: 5px 5px 10px #cfcfcf;
-webkit-box-shadow: 5px 5px 10px #cfcfcf;
}

This all worked very good until I uploaded the entire theme to github, and then back down to my Computer.

Since then, not even a MAC Time Capsule Backup solves the problem.

The problem, if I change the timeout: 5000 to (which before was possible) timeout: 2000 or any other value, the message des not disappear any more and takes very long to show up.

Does any body have a idea what this could be?

I tried even a scratch version of options page.

What can be the issue for it stop work all of a sudden, even browser crossing?

I tried also MAMP Restar, fresh folders, fresh instal...

I really hope somebody can help me put here :)