Hi Mehdi,
1. You can still see the menu item for the blog page so the user can click that. Also you could enable breadcrumbs on the page.
2. I think this is a limitation to the solution that Asad Samarian implemented to try to support Persian Dates in the blog. If it detects the culture then it uses different stored procedures that adjust the dates to the Persian calendar but apparently it does not solve all issues. Persian calendar is not well supported by the .NET framework unfortunately.
Best,
Joe