From what I recall they weren't able to make the armor, though they did manage to make plates they could insert into the vests that could dampen staff blasts, though it wasn't perfect.

Also there is a limit to how much energy the armor can absorb, a Ha'tak's staff canon can most certainly blow away a Kull.

You could say the same about the Ori Type of Shielding Technology.

On a distance, they look impossible to breach, but after the Asgard did upgrade on the beam weapons, the Ori Ships had been easy targets.

But Kull Warrior Armor is useless against the Kull Disruptor.

But the ori probably wouldn't be using it

But the Ori didn't really bother helping their followers, I am sure, countless of the Priors did report to the Ori on the flaw on the Shielding Technology.

Also it's risky messing with a technology, that isn't entirely re engineered for example on X-301 Interceptor.

The sad thing is they pretty much underused that armor, and it was most effective, there was a dude i want to say in season 3 who was immune to zat gun shots and it was the armor he was wearing which might be the first version of this energy resistant armor tech and possibly where Anubis obtained this armor to reengineer, the guy was an bounty hunter who's race was immune to goa'uld implantations.

Anyway going back to the armor topic, i just thought it was weird that the Ori didn't attempt to upgrade their gear when they came across superior gear or tech, i mean it only makes sense that's what you would do to always keep yourself at the top of power, they did it with the stargate when they created an super gate but not much else.

I mean the SGC could have just as easily done the same thing, they had a suit of this armor as well, and they could have figured it out and created armor specialized for their SG teams.

And it's not like the armor was destroyed where they couldn't obtain it and figure it out.

While it would've been useful, I think all Kull sets were sent back to labs like Area 51 for testing and not used in combat situations where untold numbers of bad things could've happened if something went wrong. Also, Jaffa-staff resistant vests were created to make their shots more survivable, although they probably didn't have the know-how on how Anubis built totally blast resistant armour yet.