Yet another update, and again I'm unable to function with the previous license key 2016-05-17_Hiatt-Richard_LRT4_profeddional.lic

LRTimelapse 5 is a major upgrade, the first since 2.5 years. All 4.x upgrades have been free upgrades and you've never had to pay for an upgrade before.
This major upgrade to 5 now, would require you to upgrade your license key. You can get the discounted upgrade on https://lrtimelapse.com/upgrade/

If you don't want to, just stay with the 4.x Version that you bought.