i used nmz a lot too. deff takes breaks and do quests and other stuff in between. and also manually train your other skills also. sorry for the late reply!

I feel like, the time you bot is also very important. Never bot after 00:00 on weekdays or during nights. Got no bans so far. I botted nmz 6 hours a day and then do something else in between. 

I think it has a lot to do with how old the account is and it's other stats/quests. If it's clear you're just doing NMZ without anything else substantial on the cave then you're gonna be at a way higher risk. For making bulk accounts to sell (e.g. Zulrah Accounts) I would personally spend money on buying low level accounts with varied low level stats in the most skills and a few quests done (not just the basic ones which give all the combat exp - include a few f2p quests with no rewards to make it look like you just like questing (Ernest the chicken, corsair cove quest, zeah quest etc.).

 

It's all about appearing to be a legit player, maybe have a few minutes of standing at the bank between each NMZ session you know, mimic a real player and you're gonna be alright.