1.Yeah, I made an error in the text file. Until the next update, if you want you can fix it by going to"Lustful Spirit Hunt_Data\StreamingAssets\mods\customnpcs\lilydomain\masuoassistantlily2EXC" and openting npcdialogue1 (or npcdialogue2 if you using second language) and look for "[/#Options:1=1*%%*2=1]". Change it to "[/#Options:1=1*%%*2=3]" and you will be able to get different reply or second option.
2.Has to be something related to second dialogue option. That one wasn't tested so will have issue. Also old NPC mod no longer work so you will need to delete them and only keep the new one.
3.Could be related to second part of point 2 since I didn't face this problem.
4.I forgot to mention, you will need to refresh custom assistant activities by cycling through truck assistants. Every time you set them to none a different interaction is selected. You won't see if immediately so you will need to go to a map and return to see if you got the new one. Alternative way is editing custom assistant "assistdata.txt".
Change "hinamasuassistoptionEXC()masuogoesghosthuntEXC&&masuohanakostreetEXC&&mrskghostdownEXC&&masuoatsughostEXC()masuohangoutwithother1EXC&&masuohangoutwithother2EXC&&doubleactionmrstEXC" to...
1."hinamasuassistoptionEXC" - Hinata & Masuo always appear.
2."masuogoesghosthuntEXC&&masuohanakostreetEXC&&mrskghostdownEXC&&masuoatsughostEXC" - For Mrs.K's ghost to appear in street level.
3."masuohangoutwithother1EXC&&masuohangoutwithother2EXC&&doubleactionmrstEXC" - See Masuo 1 and Masuo 2 double teaming Mrs. T. in street level.