You are creating a Site Files Only backup archive. Please read
the documentation.
At this point it should be fairly obvious that the Site Files Only backup archive does NOT include a restoration script in the backup archive
as designed and documented. Remember that the restoration script is included in the archive's "installation" directory. Since the Site Files Only backup archive lacks a restoration script there is no "installation" directory.
Furthermore, as Kickstart itself tells you when it starts up, it is a tool to extract any kind of JPA, JPS or ZIP backup archives. It merely extracts the file. It
DOES NOT know what is the structure of the extracted file, how it was produced etc. After the extraction it will always display the "Run the restoration" link which always open a window to the static relative URL "installation/index.php". Of course you clicking on that button will only make sense if you are extracting either a
full site backup archive taken with Akeeba Backup or a Joomla installation ZIP file. In any other case there is no "installation" directory being extracted so, naturally, trying to visit that URL will lead to 404.
Therefore what you are describing is the intended result of the combination of settings you have applied and actions you have taken. It is completely unrelated to using off-site folders inclusion. Any Site Files Only backup archive will NOT include an installation directory
by definition. If you want to include a restoration script (the "installation" folder) please use a Full Site backup archive.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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