Hey.
First off, welcome to the site.
Now, to answers your questions, yes, you do need to ask permission to use certain characters. Specifically those created by other members of the site. Though famous characters (Like Nami from One Piece) you can do whatever you want with. So since Officer Juggs, Gloria Gazongas, Geek Girl Gwen, and Nancy Boobitch and all original characters, you'll need to ask the member who created them for permission to use them.
Though there are a couple pf problems with those characters. With Officer Juggs, you should know her creator (Serrated) doesn't let anyone use her for any idea of she's going to be involved in any of the sex scenes. At best you can use her as a background character of for story purposes, but that's it. And it would be polite to still ask for permission. And with Gwen, her creator (Haseo) is no longer a member of the site, so he's not around for you to ask. As for Gloria and Nancy, I can't remember who created them.
As for a template or guidelines, the way it works is that all the premium members can submit their ideas for a vote, after a few days the submission period closes and the voting begins. The winning idea will be added to the production list and eventually made into a new game.
If you go to the main page you'll see the link at the top called called
"Vote for Game Ideas". If you click that you'll see the ideas currently being voted on. But when the voting ends the link will change to
"Submit Your Game Ideas", and there'll be a couple of boxes where you can post your idea and it's title. There are a few rules all submissions need to follow, but I can't remember what they all are off the top of my head. But basically their things like no incest, no bestiality, no rape, stuff like that.