@Jacques00 , it should be ready to be pulled now. If there's anything wrong with it, I can try and fix it when I wake up.
There were issues with numerous typos, repetition/echoing, and certain conditions being overlooked. Nik _van_Rijn noted most of them in the document. As you did with penises, vaginas can be multiples too, so you didn't need to write it assuming just one exclusively. There is no need to edit these right away as I have corrected them while adding the changes to the item.
As a future note: mentioning clothing is complicated because not only do you have to account for layers of clothing (underwear and armor, and if the character is wearing none, either, or both), but whether or not each layer is exposes a body part (if worn at all). So mentioning tenting bulges or rubbing against a genital will require a crotch exposure check and alternate lines to take account of such. Taking clothing off will require nudity checks--it gets really jumbled with all the combinations, but I figured it might be helpful to bring up just so you are aware.
The planet unlock isn't necessary anymore, but reading the Rubber-Maid codex should unlock the item in Ceria's store. I've also slashed the base price in half. As for the bad end, I don't think the vagina is ever explicitly mentioned, so I only made the lubricated skin, tongue, and cock a prerequisite (if asshole is ever added, that will be a prerequisite as well). If you modify the ending to accommodate male, female, herm and sexless, the prerequisites can be more flexible, but for now, it looks like a penis is mandatory (like have dick-less characters grow a natural dick or have them omit the line explicitly mentioning a natural dick).
Unfortunately, no. Assholes don't get flags like the other body parts covered in the TF.
Assholes are treated like vaginas (using the same class properties under the hood), so yes, they are able to obtain flags. Currently, in-game, only the pumped flags will change their external appearance (donuts), and can be modified using the Anusoft item. They may be able to adopt other flags as well (like nubby, ribbed, etc), they'll just require appearance description blurbs and an adjective list (not that assholes are described internally as much as vaginas are). Even if the flags aren't utilized mechanically, it can still be purely cosmetic (like the pumped flags).
So if a lubrication scene for the asshole is written, it can be added in like the vagina and cock scenes, no problem. I've already updated the appearance blurbs for both vaginas and assholes to account for the lubricated flag, so there won't be any issues there. If either orifice has the lubrication flag, their wetness will automatically be at least a level 4.