Hi everybody (I assume more people will look for this in the near future). PHP 5.2 is very old and any support for it from the php developers had ended more then 5 years ago https://php.net/eol.php.
Some of the features that were used in that version have been deprecated from the PHP language or considered a bad coding practice with better alternative introduced in later versions. As the people that still use version 5.2 represent a very small minority in the wordpress community (less then 10% according to this page https://www.ads-software.com/about/stats/) We decided that at this point in time making our code better for the 90% is more important then keeping it working for the 10%.
We apologies for any headache this may cause you, but frankly it is better for you to check with your hosting company how can you upgrade the PHP version that you are using, and not only in order to use this plugin. PHP 5.2 should be considered insecure now, and for your own sake you should upgrade.
