I'm running cm unofficial rom for a longtime.
I'd read @mike2nl's post about some sensors not working sometimes in forum on @storm31's rom today.
The issue not only happen's on this edition, but also happened on almost all cm rom.
I noticed that it happened in case of: when you fixed your real location by use some apps that require GPS and compass work together(such as Google maps or something like it), the magnetic sensor went not working first, then you'd find that the other sensors as @mike2nl list in forum not working ether. But the GPS goes still working.
Reboot device can set them to original type: they do can work singly.
For i'm not a developer, i didn't register in Xda site and didn't say anyword here about this.
I read you were discussing this issue today, so i registered today to submit my finding.
But i cannot reply in forum, so only post this here.
Hope you'll notice it and hope it'll be useful for you.
Thanks for all your nice works for our old SGTs!
P.S. @storm31's cm11 ron edition 05-12 has a issue: it seldom lost desktop icons after reboot device.