I've been trying a bit more, without much success;
From this I extracted the system image and tried grabbing some google services files to push to the emulator, with little success.
I referred to other lollipop gapps packages as suggestions for which files would likely be needed, although some were different.
For instance /system/priv/apps/PrebuiltGmsCorePano seems to throw up the most problems. Pushing just this, GoogleServicesFramework and framesworks/com.android.location.jar results in the system booting, but just a number of popups that the processes have failed. More packages cherry-picked basically just result in more process failure notices.
I always did a wipe data and reboot after pushing some packages.
In logcat the errors seem to be related to the matching odex file (which did get copied from factory image)
I/art ( 1250): DexFile_isDexOptNeeded failed to open oat file '/data/dalvik-cache/x86/system@priv-app@PrebuiltG...@PrebuiltGmsCorePano.apk@classes.dex' for file location '/system/priv-app/PrebuiltGmsCorePano/PrebuiltGmsCorePano.apk': Failed to open oat filename for reading: No such file or directory
I/art ( 1250): DexFile_isDexOptNeeded file /system/priv-app/PrebuiltGmsCorePano/x86/PrebuiltGmsCorePano.odex is out of date for /system/priv-app/PrebuiltGmsCorePano/PrebuiltGmsCorePano.apk
I/PackageManager( 1250): Running dexopt on: /system/priv-app/PrebuiltGmsCorePano/PrebuiltGmsCorePano.apk pkg=com.google.android.gms isa=x86 vmSafeMode=false
I/dex2oat ( 1912): /system/bin/dex2oat --zip-fd=5 --zip-location=/system/priv-app/PrebuiltGmsCorePano/PrebuiltGmsCorePano.apk --oat-fd=6 --oat-location=/data/dalvik-cache/x86/system@priv-app@PrebuiltG...@PrebuiltGmsCorePano.apk@classes.dex --instruction-set=x86 --instruction-set-features=default --runtime-arg -Xms64m --runtime-arg -Xmx512m --compiler-filter=interpret-only
E/dex2oat ( 1912): Failed to open dex from file descriptor for zip file '/system/priv-app/PrebuiltGmsCorePano/PrebuiltGmsCorePano.apk': Entry not found
I/dex2oat ( 1912): dex2oat took 203.864ms (threads: 2)
I haven't dealt with these dex/odex files before, does anyone know if there's a way to fix this problem?
Cheers.