I had a bunch of issues with BT since the x220 had it's own BT3.0 daughter card and I went through various configurations with and without it installed on the motherboard. The main issue was that the BTDC (I believe) was taking precedence over the BT on the aw-ce123h. I eventually got the BT on the aw-ce123h to take precedence by disabling it in windows and rebooting into OS X. I think both devices now power up during POST and get detected in OS X. I also ended up using USBInjectAll.kext and a custom SSDT to disable the USB port disable the USB port that the BTDC was connected to. I had to do this because the BTDC would override the aw-ce123h when resuming from sleep. Now with the USB port disabled, the BTDC is effectively disabled.
1) Install USBInjectAll.kext
2) Grab the SSDT-UIAC-All.dsl file from:
https://github.com/RehabMan/OS-X-USB-Inject-All
3) kept only the following ports: HP11 (left rear USB), HP12(left front USB), HP13(BT on aw-ce123h), HP22(right USB), HP23 (fingerprint reader), HP26 (camera). Other ports may be used if you have a dock. use ioregistryexplorer to see what you actuall use. I removed HP24 which is where the BTDC was on.
3) Used MacASL to save as AML, installed into EFI/Clover/ACPI/patched
Airdrop, handoff, continuity, all works now... awesome....