الجواب وبالله التوفيق
1- If there is a mistake that warrants performing sajda sahw, then even while reading sunnahor nafl salah it is mandatory to perform sajda sahw.
2- According to maslak al-Shaf’ai, it is permissible to read the sunnah after completion of fardh.
3- Qadha is only offered for fardh and wajib not for sunnah.
4- You should make a daily habit of reading kalamah-tayyibah and durood-sharīf whether you view the pictures of Ka‘bah and Rawdha or not. However what you are doing is also considered correct. The naqshyou have shared contains words called ‘Huroof-e-Muqatta‘āt’, which are the words from the beginning of several surahs. Some of the mufassirīn have mentioned that these are from amongst the names of Allah Subhanahu Wa Ta‘ala and are considered al-Ismal-adham. Therefore it will be beneficial if one reads them. By only viewing them, one will get the reward for only viewing as these are verses of Quran and just viewing the verses of the Quran are a means for reward and ibadah. Therefore in addition to viewing make a habit of reading them as well. Such naqushetc. are from the experiences of awliyaand has not been mentioned in any ahadithof Rasulullah Sallallaho Alyhi Wasallam.
5- In maslak al-Shaf’ai intention is only needed at the beginning of the wudhu, repeating the intention while washing the arms etc. is not required. Performing the intention only once is needed.
6- It is impermissible to play poker.
7- You can read salah behind a Hanafi imam.
8- It is not necessary to repeat each dua 3 times.
9- In maslak al-Shaf’aionly saying Bismillah is required before performing wudhu.
10- The sunnah of Rasulullah Sallallaho Alyhi Wasallam is to read it once and not three times.
واللہ اعلم بالصواب