Can you take a Reflex Recorder for a skill group the charecter doesn't have, if for example i have Pistols 3 Long-arms 2 and Automatic 4 can i take a recorder for firearms group an get +1 to all of those skills.

I don't think the recorder cares if you have the skills or not, so yes, you can take a recorder for any skill or group, even if you don't have that skil or group...

Yes, but you gain no benefit from them. They increase your skill by 1, but your maximum augmented skill rating is 0 (1.5 x 0 = 0).

That's true, you'd need a skill of 2 to benefit from it...
Do reflex recorders work with skillwires?

This whole max modified skill rating thingy might be true, but Reflex Recorders grant a bonus, not a modifier, so they are not affected by this limitation.
Ignore that, I just re-read the errata.

Some errata updated them to give a skill bonus.

Look ! Something shiny !

they should. skillwires give you skills, reflex recorders improve them.

Hmmm, barring book/FAQ quotes, I'd say that's debatable. I'm not saying you're wrong, but I'm betting someone will.

Something else I'd throw out there is that if you have bonus dice without a skill, you would still have to default

I do not take it that Reflex recorders add to Skillwires. This is debatable, but I will stand that the reflex recorder augments the neural pathways (it is cultured) that skillwires bypass. There is also the balance issue (Skillwires are capped at 4 for a reason).