Existing worlds will not load. When starting Minecraft, the main screen appears. Tap Play. My list of worlds appears. I have two, one survival approximately 411 MB and one creative approximately 65 MB. They were created using the same seed. When a world is selected, the message window appears. Resource packs load. The green status bar appears and lights up slightly less than half way, then disappears. The ‘generating world’ window appears. The pithy messages keep appearing in the message box. The background nether graphic stops it’s animation. The messages keep updating. The longest I’ve waited is roughly 5 minutes. The worlds don’t load. I am able to load a Jig’s Redstone adventure world I downloaded to learn redstone.