I think that the CheatMod by @kristof1104 should do what you want. Although you can unlock all topics only (so you can’t say I wanna have only 5 unlocked). You might kindly ask kristof if he is willing to implement a feature that would allow you to select the amount of topics to be unlocked, if you’re interested in that feature.
If kristof doesn’t implement it, let me know, as I could provide your desired feature. But using the CheatMod should give you all you need. As far as I know, he has also implemented “sequels”, “multiplatform” and “casual” from start.