Known Issues
More permanent solutions are being worked on for these issues, here are quick temporary solutions:
1. Flickering with high-detail noise patterns when viewed from a distance.
See Anti-Aliasing and Filtering. Baked textures do not have this issue.
Procedural normal filtering and distance-based LOD for the procedural shaders will be coming in a later update, which will completely remove the flickering.
2. Cubemap Preview during baking showing a seam between faces
This is in fact a repeated face. This might happen if any changes have been made to the shader just prior to baking:

This only affects the preview image and will not carry over to the final rendered image and can be ignored.