We do not have an admin option for the blog post/page comment dates so to remove these dates you would need to do some modification of the PHP templates within OptimizePress. Here's how you would do it.
1. Go to Appearance > Editor on the WordPress sidebar
2. Look down the left menu for the functions.php template
3. Once you have loaded the code for this template, search the code (CMD + F / CNTRL + F) for :
<?php echo ($postcustom['_launchpage_disabledatewpcomments']) ? '' : time_ago(); ?>
(this is on line 252 of the functions.php file)
4. Remove this line of code and save the functions.php (please note if you have strict security settings on your server you may need FTP details to confirm this change
5. This will have removed comment dates from your site. Please note because the comments system is a sitewide code - it will mean that all pages and posts will have comment date removed. Please note also this does not affect Facebook comments a we have no control over their dates as the code for that is within their system
Unfortunately because this is a custom modification of the theme we are not able to provide further support on this but hopefully the above information will be enough for you or a programmer to make this change for you.