The vent holes are there. They're under the locking ring. Look closely at the locking ring, it's notched out inside to allow air flow even when the locking ring isn't screwed down. I've had many Nemmys. Always was my favorite mech (probably gonna pick one up again due to the impending regulations. I was stupid to throw mine away). If for some reason, you think that the airflow through the vent holes isn't working properly, throw it away. Don't compromise safety.
Speaking of safety, STOP USING THAT THING RIGHT NOW!!!!! Because you don't know what you're doing. I'm not saying this to be condescending. I'm saying this to keep you from exploding your face. You know all those stories you hear about ecigs blowing up? Well these are the ones that generally do that, when they aren't used properly.
So you don't know how to build coils. I don't really care about that. Many of us may or may not build our own coils for whatever reason. But you need to understand what a coils build means. You need to understand how resistance relates to battery safety. You can't just pop any resistance atty on any battery and call it a day. Furthermore, a build that's safe on a fresh battery, may not be safe on a battery that's almost dead. Do you know Ohms law? Do you have a device to check the resistance of your atty regularly? No? Then you shouldn't be using this device.
Go back, and read the guides other users have posted for you. Read them, read them again, read them until you understand them. Bookmark the resistance safety by battery and charge chart. That will always be useful to you. Go buy a multi meter to check your battery charge, and a resistance meter so you can check the resistance of your attys (you can do this with a multi meter, but it's a pain in the .... and both devices are really cheap). This is not difficult knowledge to learn, in the slightest. And I have faith that you'll pick it up just fine. But it really is necessary knowledge.
Just having the vape shop build you a coil that should be okay on your battery isn't good enough. You need the ability to check that atty every day, multiple times a day. Because the atty might get bumped, the coil might move slightly and make contact with the side of the top cap, or the build posts, then you have a short. The wire might break. Things can happen. You have to check your coil regularly. Even if you're using a factory built coil in a tank. Things can go very wrong. A short puts you at risk for a thermal runway. You don't want that. And vent holes won't save you from a whole lot of bad juju. Yeah they keep your mod from becoming a pipe bomb. They do not keep your battery from failing spectacularly (hot battery internals are not something you want anywhere on your body or in your general vicinity).
Your other mod is a regulated device. It has a computer that shuts things down if anything goes wrong, like a short. Your mech mod does not. You have to manually regulate your device. Until you have the knowledge and willingness to use it safely, for your own good, please don't use it. It's not worth the risk. Always respect the limitation of your hardware.
