Do you tried to install apcupsd in Zeroshell 3.2.1?
Maybe kernel 3.4.90 or 3.14.21 has USBHIDEV module?
I have same problem, i need use APC with Zeroshell, but i`m beginner with Linux, and i dont know should i try to install apcupsd in 3.2.1 release or not, because it would difficult for me.
Thanks in advance!
P.S.: Can apcupsd running on ASUS RT-N16 correctly shutdown Zeroshell box when power down? apcupsd daemon doing it via net?