In case you can't Re-install Tickera pages make sure you have permanently deleted pages even from the Trash and try to Re-install pages again.
If this doesn't help you will have to create Tickera pages manually. Make sure that each page contain necessary Tickera shortcode:
[tc_cart] - For Cart Page
[tc_order_details] - For Order Details Page
[tc_payment] - For Payment Page
[tc_order_confirmation] - For Payment Confirmation Page
[tc_ipn] - For IPN Page
[tc_process_payment] - For Process Payment Page