Also, listed in the CRL's it states "Armor should have an organic feel to it. It should appear to be bone, leather and/or rough pounded metal." Metal
is acceptable as long as it has a primitive "ancient" feel to it. In all honesty, there isn't a whole lot of metal seen via the comic (Tales of the Jedi The Sith War) on Mandalorian warriors at that time. Some of the weapons like the Ripper and Mandalore's axe and the Bes'uliik droids for example. But, at this moment, I can not recall any shown in metal armor. But, that doesn't mean there wasn't any which is why we allow that as an approvable option.
In regards to your rebreather (which I assume this post was made in response to) it neither follows the metal guidelines or colors set for the era. As your blue and red accents are not acceptable for the era.
Yes, they did have lightsabers during that time, like you said. But, they didn't look like a Modern lightsaber either. They
looked primitive or "ancient". As seen below.

Even the Jedi's armor at the time had a primitive look to it.
I'm not trying to argue or start a fight just state the facts on why the CRL's are the way they are as the last revision in 2013 was done by myself the previous PO and member of the Approval Team. Which is why I brought it up in you WIP thread. I know the rules front and back for this era and continue to help the team keep an eye on the boards here even though I have stepped down from any official position.
Also, you have to remember we are here to costume a character of a specific era and we want that to plainly come across. We want people to just be able to look at an EC and
know they came waaaay before any Fett donned a helmet. After all the Early Crusader Mandalorians were the very first Mandalorians and that is clearly shown in their armor and weapons. They were primitive compared to todays Modern Mandalorian. Just like Cavemen are primitive to Modern Humans.