For once I can actually give some proper tech advice on something instead of just giving opinion!
The air is probably coming out of the hole around the valve because you haven’t nipped the lock ring up enough. The rubber bit on the valve inside the rim is designed to fill the gaps but if the compound is quite hard it may not deform enough to seal it initially. I had to use pliers to get it tight enough on our test rig when we were testing the new tubeless valves we were looking to distribute. It was the first time I’ve gone tubeless and found it massively demoralising until we got it sorted.
It’s really hard to fully inflate the tyre with air leaking out at the rate we had (and it sounds like you have) and so the sealant doesn’t go where you want it to go for long enough without the tyre going down. Once the lock ring was ultra tight we had no problems inflating the tyre.
The trick is to back the lock ring off a little so it’s finger tight once the tyres have sealed, otherwise you’re knackered if you do need to put a tube in.
I also found that hammering the bike around Cwm Carn seated the tyres nicely and now they hardly lose air at all. So chuffed with the valves and sealant that we are going to distribute them!
Sits back with brew and biscuits and waits for the collective to tell her she’s wrong…….
Edit: check out PinkBike.com – Technical Tuesday: Tubeless Conversion for a really clear How to video that also says how long it could take to get it to work. The valve lock ring thing I suggest is from personal experience not PinkBike.