When I went to visit some ancient synagogues in Israel (4th century - 6th century) a few of them have mosaics on the floor with prominent and beautiful pictures of the zodiac - all 12 signs with pictures identifying each one. Was the concept of the zodiac and its role in Jewish life such an important factor in Jewish life back then? What role did it play in day-to-day life that made it important enough to be the centerpiece mosaic on the synagogue floor of various synagogues?
The Sefer Yetzira (sefer which the Bnei Yissaschor bases itself on, which is itself relied on for Wisdom of the Months by Rav Ryzman) the concept of each shevet being represented by each of the twelve mazalos. Seeing that each shevet had it's own pathway to serving Hashem (Emes l'yakov by the mishkan) through tefilla, hence the custom of having 12 different windows in a shul as there is a path to connect with Hashem through each shevet, it makes sense that the shul focused on the mazalos. Moreover, see Shabbos (119) which discusses the affect each mazal has over the personality of an individual based on which constellation was strongest when he was born.