1) Are there other instances where these noun-cases are found?
Yes, there are many other places where these cases are found. They will be discussed in later levels.
2) Are patterns or roots more important for determining the meaning of a word?
Both are essential to understanding what a word means and a student cannot do without memorizing both a large number of roots and a large number of patterns. A root on its on will only give you the general underlying meaning and the pattern will focus it into a specific meaning, such as an active participle (doer of an action) or passive participle (the thing or person to whom the action is done). Both of these patterns will be discussed in the next lesson more in depth and in Level 2 later on in the curriculum we will learn additional patterns.