Your SAD doc is too long to read through in a short period.
Too much documentation can kill the documentation! But you do not need to read the whole document: most of it is a detailed description of every unit, object, or class. But the first part is worth reading, otherwise you are very likely to miss some main concepts or patterns. It just takes 15-30 minutes! Consider also the slides available at https://drive.google.com/folderview?id=0B0r8u-FwvxWdeVJVZnBhSEpKYkE
Too much documentation can kill the documentation! But you do not need to read the whole document: most of it is a detailed description of every unit, object, or class. But the first part is worth reading, otherwise you are very likely to miss some main concepts or patterns. It just takes 15-30 minutes! Consider also the slides available at https://drive.google.com/folderview?id=0B0r8u-FwvxWdeVJVZnBhSEpKYkE