Ok guys new updated ROM is ready to go!
As I metioned before it includes some changes to USSD stack. In my country (PL) most codes are working correctly now but some are partially cut

Anyway it's more better now
Bluetooth work all the time without any issues. Hope it will work for u guys too!
ROM has 3 locale now: pl, en, zh_cn
I have added a little cherry from new Google child.
Download:
cm-12.1-20151008-EXPERIMENTAL-BuGi-aries.zip
It maybe necessary to reboot device twice after loading ROM.
Let me know what do you think!