Do you have script mods enabled in your game settings? If not, these mods will not work - at least MCCC won't. Make sure you have script mods enabled and that your mods aren't in too many subfolders - script mods can only go one folder deep. If MCCC works, you'll get a notification that says "Welcome to MC Command Center Version ..." as soon as you load the neighborhood. Then go to a household with a computer, click on the computer, and make sure to disable culling. Now, I don't know where the MC setting to disable culling is at, so I suggest you go to the mod's Tumblr site and read about it and its modules. Hit ctrl + f, type in culling when you're in the documentation overview and you should be able to find where the culling settings is. I have no idea how that other mod you mentioned works, though. I only know MCCC and I know just putting MC in isn't enough; you have to click on a computer, go to MC Command Center, find the culling setting and manually disable it.
Edit: If you don't want culling disabled altogether and you successfully downloaded MC, you can also type in mccc simfirstname simlastname and it'll show you the Sim's menu. Go to Sim Flags, search around a bit (again, I don't know exactly where the setting is), and there should be a setting to "flag for no culling." If you go with that one, that specific Sim will never be culled. You could do this for those family members who keep getting culled, and MC should protect them!