Everything looks good to me but these two. Remember that when you change a sentence to the passive, you need to change the ‘person’ of the verb to fit the new subject (which was previously the object in an active sentence). This involves changing not just the voice of the verb (laudant->laudantur), but also the person and number (laudo->laudatur).
So “Carmina poetarum non tantum legimus sed etiam ediscimus” in the passive becomes “Carmina poetarum a nobis non tantum leguntur sed etiam ediscuntur.” In the active sentence “nos” is the subject, but in the passive the ‘carmina’ become the subject, so the verb must take the third person plural.
Similarly, “Memoriam nostri servatis” should become “Memoria nostri a vobis servatur.” The memory is the new subject, so the verb is third person singular.
Ah, it was in a hurry written, I just wasn’t concentrated.
You will see that in first sentence I put right verb form, but in second and third I was just lost concentration in hurry.