Hi does anyone understand this? 
ive sended an email to activision to ask if i may convert xlabs from the rtcw single player to et :
Response (Monica Beizaie) - 04/14/2006 09:14 AM
Thank you for contacting customer support. Activision does not provide support
for the map editor or other components of the SDK.
An editor - or SDK - is available for this game. The SDK has not passed through
our quality assurance program, and as such we can make no guarantees of it's
functionality or performance. If you have questions about the SDK you will need
to review websites dedicated to the game for solutions. Beyond general fan
pages, many sites are dedicated to each specific editor. These resources may be
your most effective for learning how to properly use the tools.
Activision also does not provide support for content created using the SDK. As
the SDK is freely available to anyone who would like to use it there is a great
variance in the quality of content. Both experts and novices will be using these
tools and releasing maps, skins or even complete mods to the game. Some will
work, some will not. If you have questions regarding any content you've
downloaded from the internet you will need to direct them to the author.
i don’t think this answers my question :s