Reverse engineering is not just an engineering task—often, it requires a certain amount of research and creativity in order to solve these challenges.
Usually, the analysis time is limited by circumstances. Therefore, pay particular attention to the functionality that will help answer the questions needed to complete the report. This part might be tricky because, without taking a look at everything, it is difficult to say whether the description is complete or not. Searching for the keywords of functions of interest and checking their references should be a good starting point. After this, it makes sense to check whether any block of code was encrypted, encoded, or loaded externally.
