Do errors in reciting Al-Fatiha, such as the qalaqalah of the letter "ha" in "ihdina" or its omission, or not extending "al-dalleen" for six counts, or vocalizing the letter "sad" in "al-sirat al-mustaqim" during silent recitation, or sounds emerging during recitation, or pausing after "an'amta 'alayhim" without changing the pronunciation of "ghayr," or pausing between "wala" and "al-dalleen," or making the last letter of a word like "al-salihat" quiescent, or sometimes pronouncing the ta' marbutah as a "ha" and other times as a "ta," affect the validity of the prayer?

The type of لحن (mistake in recitation) that invalidates the recitation of Al-Fatiha is the blatant (jali) one. As for the subtle (khafi) mistake, it does no harm. Omitting some of the recommended rules of Tajweed (definition) does no harm and does not affect the validity of the prayer. One should adjust their recitation by a trustworthy reciter. Speaking some letters aloud in a silent prayer does not affect its validity. Pausing at (عليهم) is permissible, but pausing at (ولا) is not advisable. The advice is to attend recitation circles, learn from a trustworthy reciter, and cast away any whisperings (waswas).