I need your help...Im a noob

[mikeybe]

My question(s) have to do with setting up a CO2 rig, but not directly with brewing. Basically, my goal is to create a system that will output from a paintball co2 tank to a sports ball needle at approximately 50psi that is small and cheap. And it needs to have something to turn it on and off (ie blow gun). I know this is a brewing forum, but you guys seem to know a lot about tanks and hoses and connectors so I thought I would come ask the expert DIYers. I know basically nothing about high pressure systems and regulators and connectors so I'm looking for some advice. Here is what I have so far.
1 paintball tank

1 co2 regulator to paintball adapter:
The Adapter - CO2 Regulator to Paintball Tank Adapter

1 227C-50 Argon, Argon / C02 mix Pre-set Regulator CGA320, 50 PSI:
GENTEC Compact PreSet Gas Regulators

1 blowgun and hose kit:
Buy 600-N12 Coilhose Pneumatics Hose & Blow Gun Assemblies from UseEnco

1 sports ball needle

What I'm not sure about is (a) will the paintball adapter fit the regulator and (b) will the regulator fit the hose kit and (c) and I missing something? I don't know the terms for the connector types and threading sizes etc. Do I need O-rings? Do I need some sort of sealant for the connections so they don't leak? I really have no idea...I've just had an idea and have been looking up parts that seem compatible. Is there a better way (remember the cheap\small factor)? Any advice would be helpful to know if I'm on the right track. I really appreciate any help you can give!
Thanks,
Mike