Id like to show you a simple technical to make animation without using a render
it's easy, what you need is just software who accept the gif files as for example the
natural illusion studio with this software, you can make animation for water, snow, and import gif files
after that you can save the animation gif or use the studio cam recorder software to catch the screen
with this technical , you can make a long video, my be more than one hour
This is an example
1 - Use Terragen to make different scenes
2 - Use Natural Illusion Studio to add gif files and do some animation like water
3 - Catch the screen with Cam Studio Recorder
4 - Put the sequences animation all in Movie Maker software to make video with sound and some mouvements.
That it.
Enjoy
To get the best quality, you need HD software as Screenpresso.