Good idea,wellcome to Urumqi.October or befor October is good.this time is golden season-people say.All the fruits are riped.beautiful scenery .and people also reach at this time. After november it is going to start to be cald. for travel June to October is good.for xinjiang.
for the transportation- no direct airline from Kualalumpur to Urumqi.
so you need to stop over Guangzhou or beijing.from beijing or from guangzhou you can flye to Urumqi.from urumqi airpor take bus No51 take of the and of bus destiny.then you will at the long distence bus station,from there you can buy ticket to kashigar.from kashigar to yerkent. from yerken to Huten.from huten to Korla . from korla to ili.and then from ili to Urumqi
I am sure you will be very happy for that journey .
Hope you enjoy your trip!

hi there
that is good idea anyway i warmly welcome to xinjing ,,,Mr osman give to you some info that is same as mine but urimqy to kashgar more then 1400km so take train better then bus << it takes almost same time and .
end of year is not so good for Mountainring area, because at time wether bit colder some times rain and snow . end of year is good for taklimakan desert camel treking and city tour .
if you want more info or help in xinjiang , contact me:
E-mail , muslim.com|kashgar
mail.com|kashgar