Error message with snapshots re: CRON JOB

Here is the message I have with all my snapshots in the Archive section:

"Your site has disabled the WordPress Cron scheduler (WP_CRON). When scheduling an archive to be created it may not run. Check your wp-config.php for the DISABLE_WP_CRON define. If found either remove it or set the value to "false"."

The reason I have this message is because I set up my own custom cron job to minimize serve load (on my shared serve). I ran this by Ash first. The snapshots are still running but are delayed by the timing of my cron job (which is currently set to 30 minutes).

There doesn't seem to be any problem running the snapshots, but I just want to be sure there is no other negative effects with my custom cron job affecting Snapshot operations. For example, If I have a snapshot set to run at 2:00pm and it doesn't run until 2:30pm because of the cron settings, will that particular snapshot request be leaving an open-ended request to my server and putting that extra load while it waits for 1/2 hour?

Thanks for your input. Joe.