Yeah, some characters have some issues (some drink/do drugs, others steal, others get into fights, others get fresh with each other, etc.). Some can be resolved (like the alcohol/drugs can be fixed by sending the to rehab and/or making them stop liking alcohol/drugs). Others like the anger or the stealing one don't have full resolutions implemented yet.
Yes, it's much much harder. It doesn't have native support so would need to rely on some plugins. But more importantly the software I used to create the images generates PNGs. So I would have to convert every image from a PNG to WEBP and vice-versa everytime I need to do something I would take way too much time. In addition, the size differences you see come at the cost of losing quality. My images are already pretty small and the additional compression savings would not be as significant. When you have a bunch of 1920x1080 images those compress a lot more than my 512x800 ones. It would not be worth it.
Are you sure you did it right? I've been running with my taboos turned on my user_config file and I have no problems starting new games. The taboos are enabled for save files too.
Yes, getting them to like you helps you talk them into voting the way you want. So if you can seduce them and that raises their opinion of you, then yes, it will help. Every law is affected by different things, which is why so commisisoners will vote for some laws and not others. So the public decency laws are affected by their opinion on public nudity and sex.