Both errors in that screenshot are telling you that the scripts you are using (this mod and this WP plugin you are talking about) are using some outdated code that could be replaced by something faster or better or more secure in some way. They are not actually telling anything has faield to work, it's just a notice for the person who made the script to update it.
I think you can force your server to ignore the error and not display it by adding "error_reporting(0);" to the top of the PHP file the error is refering to. (After the "<php" tag. )
I'm not too good at PHP myself, but I think that will work. (untested)
It's sort of notice is more likley to happen when you are using a really bleeding edge new version of your webserver with PHP addon.