Welcomed by whom? Certainly western nations would have welcomed any new ideas or weapons, especially repeating crossbow(although it was not the most effective of weapons), China would not have allowed it to leave the country.

The only way i could see military technology leaving the country, would be if the artisan suddenly upped and left, or someone came across the blueprint to make the weapon. The weapons themselves were most likely well guarded day and night in the armory in order to prevent tinkering or common soldiery running off with them. The only way the west could have gotten a hold of them was if a Chinese kingdom lost a massive war and it was transmitted from nation to nation all the way to the West (Although each nations would most likely guard the secrets as well, making the transmission of the knowledge very hard). It is unlikely that artisans or court officials would suddenly up and take the knowledge and run off elsewhere, especially military technology. Not to mention, the state it self would make sure the military technology did not fall in to the hands of foreign states. This would make importation of Chukonu very hard for western kingdoms.