I will tersely answer the second question - they weren't more accepting of outside knowledge than the Chinese (who were key 'outsiders' from whom the Mongols took tech and knowledge), they were simply more widely exposed to the greater Eurasian communities due to their expansionist methods.
For the first, I am not so great on the tech end of the mongols. Someone else will have to jump in on that. However, you might want to read some of Morris Rossabi's work on the subject. That is where I would go to find your answers.

Last year there was an article published in the Journal of the Royal Asiatic Society 23(3), pp. 441-469 about the Mongol adoption of military technology in China. A pdf of the article can be found on academia.edu. This is an excerpt from the article:

The success, speed and range of the Mongol conquests were not simply the result of efficient military organisation, excellent generalship and exceptionally effective use of traditional steppe nomad weapons. Cavalry armed with bows and arrows could not possibly have taken walled towns, cities and fortresses as easily and rapidly as the Mongol armies consistently did,during the early period of their conquests. The Mongol conquests were essentially enabled by Chinese artillery and Chinese gunpowder weapons. It could, in fact, plausibly be argued that the Mongol empire was the first of the so-called ‘gunpowder empires’. As to whether the Mongols used guns, the evidence is that by the late 1200s they certainly did and it must at least be likely that they began to use them earlier. The use of guns, however, is not the essential issue. The range of Chinese gunpowder weapons available to the Mongols, such as explosive and incendiary bombs, fire-lances and fire-arrows, was sufficient to inspire terror in enemies who had never previously encountered anything of the kind.

I would also recommend Allsen's "The Circulation of Military Technology in the Mongolian Empire" in Warfare in Inner Asian History (500-1800), which covers the exchange of military technology throughout the entire empire and not just China.