Z33 and jas0nuk have managed to unpack the headers of the 3.40 RCOs.

More info here: http://forums.maxconsole.net/showthread.php?t=59127

EDIT:
Z33 has certainly been busy.
All 3.40 decompressed RCOs (2.22MB)
3.71 All in one RCO archive attached.

(This post was last modified: 03/10/2007 01:11 PM by |-Anubis-|.)

does this mean wee can finally decrypt/decompress 3.40+ rco's?

Yes.  I want to know how the RLZ compression works though...

WHAT!!!!!!!!!

OMG!

*regains composure*

so how soon do you think this will be useful?

Can wee edit them with the current RCO editor?

^^Maybe, you'll probably have to merge the header into the 3.40 RCO - icons will show up invalid, but replacing should work.  Not certain though, the 2.70+ RCOs rearranged the text data, so if the RCO contains text, it probably won't work.

are the headers the only things that can be deflated? or can the whole rco be deflated?

the headers are the most important part of the RCOs.

I'm thinking that it would be ok if none of the icons were decompressed.

Although it would be extremely useful.

Great news, just have wait now.

I think the headers and icons are probably compressed the same, but IDK.

The text data does look like it has the same compression method as the header.

OMGOMGOMGOMGOMGOMGOMGOMGOMGOMGOMGOMGOMGOMG! *head explodes* O.O

This means it should be possible to update RCO Editor to work with real 3.40 RCOs, right? No more random graphical errors or weird anomalies!