On May 14th 2020, a hotfix was released for the Guides HoloLens and PC applications (version 400.2005.13001.0) to address an issue with the animation toggle on the most recent version of Guides release April 28th. We became aware of the issue on May 12th. 

The issue impacted 3d assets with animations that were authored prior to the April 28th release. After upgrading to the 400 versions of the Guides apps and solution, assets that had animations toggled ON were no longer animating and assets with animations that were set to OFF were set to ON. This nas been resolved with the hotfix release. 

Please note that with this fix, any 3d assets that have animations set to ON that were authored between the April 28th release and the May 14th 'hotfix', will have their animations turned off and vice versa for animations that were set to OFF will now be playing. You can turn these back on through the animation toggle in HL authoring mode (https://docs.microsoft.com/en-us/dynamics365/mixed-reality/guides/hololens-app-orientation#turn-off-animations).

Sorry for any inconvience. Please let me know if you have any questions or further issues.