The asshole and fansubber in me just wants to groan and tell everyone how stupid they are for shutting down due to someone getting upset. I don't think I have ever dropped a project due to threats and I do anime, you know the companies that actually have SOME pull and release outside of Japan.
The other part of me gives the following the advice. Keep in mind nothing is most likely going to happen because if companies had that kind of time, money, and influence we would all be fucked already 10x over. However if you just want to be safe here is some advice. However I do think its going a bit overboard for H-manga but better safe than sorry.
1. Host all your servers overseas.
This includes websites, ftps, anything else you feel like using to distribute. Europe is a good country. OVH is a good company to use and is generally good. PRQ for the extra paranoid. There are probably others too but are either too expensive or I don't know anyone who has used them so I can't really comment.
2. Don't reveal your sources ever
You know that guy who uploads everything for everyone and actually lives in Japan? Make sure no one knows who he is.
3. Use the server for any and all uploading.
Since scan groups seem to have some hate for torrents I would suggest that any and all uploading you to do a website is done using a server or a
vpn that does not store any logs. In the off chance something does happen and they request from the site admin for IPs and the admin actually gives it up, they won't get shit from them that is useful.
4. Don't credit yourself or host a website at all
See number 3. Your goal is to release things to the public not internet fame.
5. Use irc for discussing anything with staff. Remember to use SSL.
Make sure you have your hostmask not visible as well. Rizon is a good place for this. Don't keep logs. Password and invite only all your staff channels.
6. Stop being retarded
Seriously. I hate having this conversation. I have it way more often than I should.
Questions or concerns? I probably missed something but this should get you started.