Odd Realm is fairly enjoyable but it does have some issues. I just managed to figure out a workaround just now for several that was preventing me from integrating captured bandits as citizens.
First was figuring out how to actually capture them. There are cage traps, but if you build them on the surface(or at least on the z-level they're on), the enemy will clearly see them and walk around. You have to build them on the z below, and a trap-door on the surface above(they don't see those). This also works for spikes.
The other issue is seizing them, which makes them "captured" members of your faction; basically slavery, you cannot change their profession so you're stuck with them as being the warrior/archer(maybe mage, but I haven't had one yet), and while you can tick skills on, they won't level up anything but their combat skills(which is what professions do). What happens is when you mark them for seizure, the character trying to seize them will often still try to attack them or especially other trapped bandits. I've managed to get them to stop by giving them another order after they're captured, but I think turning off the combat skills will also work. I haven't tried.
The last issue was giving the integrate job. It's unlocked from the prison tech, but requires the town hall tech(and room) since the town hall is the one with the job, not the prison. It also requires a table(Wood-work tech) in the town hall, and a supply of paper and ink, which are unlocked via the Library tech(but made in the workshop room). The problem I found was that the town hall room doesn't have its occupancy permissions set correctly by default. Apparently you have to flag them for both citizens and captured people(other rooms do not seem to require this). Also, the integrate job claims to require hauler as a skill, but it's the write skill, as I figured out through ticking every skill. Then there was still trouble actually getting the bandits to integrate, as the job kept cancelling itself.
I have seen a post by the dev that they're aware of the issue, but there hasn't been any fix in the last few patches.
EDIT: Found another issue regarding recruiting captured bandits. They don't receive the abilities to eat and drink, resulting in starving/dehydration. This one can be fixed by simply saving and loading.