Sajda-e-Sahw

Leaving out a Waajib in Salaah

Q: A salaah in which a wajib was left out, it is wajib to repeats within its time. But what if the time is over, is it still wajib to repeat it. Also such prayer can it be prayed at any time like after few days or is the order to pray it befor the next prayer obligatory? Do all makruh tahrimi acts, like omitting wajib, prayed with pictures on the cloth or towards a picture make it wajib to repeat the salaah? Or is it in some cases only sunnah or mustahab to repeat it?