Hey Mikosan,
first of all, thank you for the purchase!
Please try creating a new page (“Pages -> Add New”) and give it a “Portfolio” layout from the “Template” drop-down in the “Page Attributes” settings box on the right hand side of the page edit mode screen. Once you save this page, it will display all existing projects (i.e. items that have been created in the “Portfolio -> Add New” admin section).
My apologies if it hasn’t been described in enough details in the theme manual, I will extend that part for the next theme update. Thank you for pointing this out!
Regarding the content importer: this part of the WordPress back-end is not connected with the theme, if you are receiving an error message when trying to import the demo content, it is most probably connected with the settings of the server you are running your WordPress instance on. However, just in case, this is what you can do: go to “Appearance -> Themes”, change the theme to some default one (e.g. “Twenty Fourteen”) and run the importer again. In case it goes smoothly this time, please let me know – I will troubleshoot further.
Should you have additional questions about the theme, do not hesitate to contact me.
Sincerely,
Andrii / Satori Studio