And through שלמה and through the sons of קרח, etc. - ועל ידי שלמה ועל ידי בני קרח
Summary:
All agree that these nine contributed to תהלים namely; אדם, מלכי צדק, אברהם, משה, הימן, ידותון, ושלשה בני קרח. Those who do not include שלמה mention אביאסף; those who mention שלמה consider אסף as אביאסף. Those who include איתן האזרחי do not include שלמה or אסף, but need to explain why we include אברהם.
חזקיה and his associates wrote ישעיה, etc. - חזקיה וסיעתו כתבו ישעיה
Summary:
חזקיה did not actually write ישעיה for he died before ישעיה; however, since he inspired סיעתו to study תורה therefore he received the credit together with סיעתו.
Eight פסוקים in the תורה, etc. - שמונה פסוקים שבתורה
Summary:
יחיד קורא אותן: according to ה"ר משולם only one person reads with no assistance; according to the ר"ת, it should not be divided.
קריה"ת: according to the ר"ת only one reads, except nowadays where both read כדי שלא לבייש. According to the ר"י the חזן assists quietly.