I will admit that this is my first glow engine aside from a short history with a .40 size trainer before I went to electric flight, so I don't have a great deal of experience.
I'm having a hard time setting the mixture. I'm on about my 10th tank and the boat occassionally stalls from one run to the next without me making any needle adjustments. It also doesn't stop when I push the trigger forward and close the carb. I followed the video and manual instruchtions, but I'm having no luck. Any help is appreciated! Thanks.

If it doesn't stop when you close the throttle, it sounds like you have an air leak somewhere. This will also show up with inconsistent runs on the engine too. Check to see if the carb is seated good and check the head and backcover bolts for any that are loose. Let us know what you find.
Suptter

The carb is not loose, but is it possible that I need to remove, reseat and reseal it? What should I use to seal it?

I have checked these boats and motors pretty closely and I think the motor is a Tower .46. You will be able to get a lot of info here if you search the forum for the Tower .46. I have noticed some very knowlegeable people here admit on some of these Tower motors the air leak and poor shut-down is something they have come to live with. I have a boat that I bought used that is very similar and it has a GP .42 which is even less expensive than the Tower. Somehow I feel a little better about the investment I made on the motor when I'm paddling out to get it while the boat is upside down with the motor submerged. Take care, Cliff

When your resealing the carb, just use some red RTV. It can be used on the backplate also, but not on the head gasket.
Suptter

I have found that my aquacraft 46 runs better on a hot short non idlebar plug. If I put in anything else I have the same problem. I never can get the mix just right and it won't turn up. Mine will turn a 9-8 apc prop at 15500 reliably with the short plug and only 13,300 with the long.

You may have too high of a compression ratio on this engine. Using a short plug would help to lower it. Have you tried using a low or no nitro fuel? I have found that a lot of Chinese engines are set up to run FAI (no nitro) fuel. One other thing you could try is putting 2 head gaskets on it. Just a thought...
Suptter

You might also search for posts about the GMS .47.