Is there a sufficient explanation of Al-Saffati's commentary, and is it permissible to believe the issues taken from the Ash'ari creed and the Mutakallimun in Ibn Ashir's poem in the chapter on belief, such as the number of essential attributes?

There is no written explanation for Safati's gloss, and glosses are typically not explained.

The Ash'ari creed contains errors and contraventions of the creed of Ahl al-Sunnah wal-Jama'ah, and it is not permissible to believe in those contraventions.

There is no objection to studying the Ash'ari creed for one who possesses sufficient knowledge of the creed of the Salaf to distinguish between truth and falsehood. Otherwise, it is not permissible to study it until one learns and becomes thoroughly proficient in the creed of the Salaf.