This document will outline what the file statuses for files, and what you can do to fix them.
Invalid Layout essentially means that the directory structure of your file is incorrect. The directory structure should be something like:
To correct this, simply reorganize your zip file and re-upload it.
.DS_Store means that you have included .DS_Store files/folders/directories in the zip file.
To correct this, remove the .DS_Store files from the zip and re-upload, or zip with the following command:
zip -r "$1" "$1" -x \*.DS_Store