Good chapter, seeing all the characters from the previous version was excellent. My little critique would be that it was a long and welcome chapter, but I felt like nothing much happened, especially after waiting for a whole year. It felt like it was stretched out for the excuse of giving us filler content, like fanservice.
Yes, WIAB and SG are very interconnected and to answer your halfquestion, "Where it all began" plays about 20 years before "Summer´s gone" in the same small city of Wollust.
Several families you will run across more than once, e.g. the Zanes, the Frohns, the Holgersons or the von Halens to name a couple.
As for some of the changes between old and new version, the biggest flaw in my opinion is mainly the optical. Why the heck are so many erotic devs hellbent on outfitting the girls with milkjuggs???? For example, the Leia from old 0.6 had very nice breasts, quite fitting her frame. That could have been kept or only a bit enlarged, not like this large.
Another change, but interesting one, is the closeness of the
relationship. In old WIAB they were already very close, but had not gone beyond kissing and fondling, when
snitched/outed them. In new WIAB the phrasing and implications from e.g.
and the reactions seem to indicate that they went a LOT FURTHER, even all the way before being found out.