A lot of questions, but I will try to help.
1. I also would like an undo hokey in creator, but don´t know myself. I think something like this was posted here, unfortunately I forgot.
2. the voices are dependent on the "Personality" you choose for your girl. Each personality is spoken by another actress. But only japanese voices available I know so far
3. I don´t not fully understand what you mean with "roams". I guess you mean the locations for H Scenes? In the Repack there are a lot af maps included in abdata/maps and mods/Sideloader Modpack-Maps. Some locations had to be unlocked first with Achievement Points.
4. Not so far I know - I´m missing it too, also a milk squirt animation
5. If you change the player character, all earned achievements of the first player remain. The state progression of the girls are saved in their cards. Therefore you don´t need several "save games".
6. sry, don´t know what you mean with "auto-modes". And regarding "Skyrim position mods": do you mean a "pose" mod (poses for character) or a "positioner" (placing objects everywhere)? Nevertheless nothing exists for the game, for these functions we have StudioNEO - there you can create your own scenes and placing your characters and available objects as you want.
Here is a link to learn more about StudioNEO
https://f95zone.to/threads/illusion...-maker-help-guides-thread.66252/#post-4529674