Does this game have loli content after the "Old Young" expansion?
There is no 'true' way to get what you're after, but there are ways to fudge the system.
The game is moddable in that most of the system files are editable with Notepad++. I recall that there is a file that can be edited to allow the age slide to go below the default age of 18(Sorry, I won't say which. Loli is frowned upon. You'll need to hunt for it. Not that difficult to search files tho...). However, the rest of the game's scene files won't acknowledge any type of situation you are looking for as all scene files have been written from the viewpoint that you are an adult interacting with adults. You can also write your own scenes. There are tutorials, triggers and such included in the docs with the game.
As for appearance,
it is no longer possible to adjust character height, but with creative use of morph sliders (go to detailed morphs, click on the
value number of the morph sliders instead of the slider itself and manually input a value from -10 to 10, decimals are also accepted). With enough work, you can get some younger looks and flatter chests(or curvier ladies and bigger cocks), but most of the skins in the game are default DAZ3D stuff with drawn-on veins for muscular guys, shadow beneath breasts and some skins having wrinkles drawn in as well.