Ok, just going to do a lust walkthrough. I real quickly ran through the game marking down lust values. There is, I think a bug in the shack, which I'll mention later (I have not spent any time testing, just noticed a discrepancy)
1. Immediately say yes to stay at the shack. 7 lust
2. Lose a fight to a monster. 12 lust
3. 2nd BJ scene. 17 lust
4. Cnal scene. 27 lust
5. 3rd bj scene. 32 lust
6. 1st time watching Irelia. 33 lust
7. Leave the green haired guy. Later, choose to reward him in prison. 43 lust
8. 2nd time watching Irelia. 45 lust
9. First tentacle scene with Irelia. 47 lust
10. 2nd Tentacle scene with Irelia. 49 lust
11. Mansion. Wine with Irelia. 54 lust
12. Hut. Closet with Irelia. 59 lust
This is where you choose the route you want to take. A = watch minotaurs B = save Kat early
13a. 1st mino. 61 lust
14a. 2nd mino. 63 lust
15a. Stay with shack man. 78 lust
16a. 4th BJ with shack man. 83 lust
17a. 5th BJ with shack man. 88 lust
18a. 2nd Anal with shack man. 93 lust
19a. Maid with shack man. 98 lust
20a. Volunteer at captain. 100 lust
21a. Final BJ. 105 lust
13b. Stay with shack man. 74 lust
14b. 4th Bj with shack man. 79 lust
15b. 5th Bj with shack man. 84 lust
16b. 2nd anal with shack man. 89 lust
17b. Maid with shack man. 94 lust
18b. 2nd Horse scene, choose yes both times. 101 lust
19b. Volunteer for captain. 103 lust
20b. Final BJ. 108 lust
Route B I just tested again with success. All values were correct. Now route A, there was an issue. I only went through it once, HOWEVER, I didn't get the 4th blow job scene, but saw the 5th. This stuck me at 95. I don't feel like testing it right now, if someone else wants to go ahead. I may do it later, but I've now run through this part of the game one too many times. One thing to know is, before you watch any of the minotaur scenes and you choose your route, you should be at 59 lust.
EDIT: OK I think I see the problem, and this probably is what's causing people issues. Note that I'm unsure of the values here. Watching both minotaur scenes and staying at the shack puts you at 78 lust, which skips the 4th BJ scene and goes straight to the 5th. I believe 75 lust is the trigger for getting the 5th scene, so if staying at the shack puts you over 75 that means you miss the 4th BJ, and thus 5 lust points. The only way to circumvent this is by not losing a battle up till this point, so that you're at 73 lust after staying at the shack, not 78. Once you've finished the scenes in the shack, proceed to lose a battle for the 5 lust. I haven't attempted this new method, as it would require starting the entire game over again.