Blender2.8 Windows 64 bits version 30/08/2018 20:49
If you add a keyframe using I key over the custom property, if you move timeline, you cannot change or animate the custom property.
- Open attached file.
- Select cube and in custom properties set "hide" property to 0
- Over "hide" property, press I to insert keyframe
- Move the timeline and try to change hide prop or insert a new keyframe
I noticed also some random blender crashes when clear the property keyframe of hide property.
I have tested the same in 2.79b and works.