Cubase LE 6 worked fine until I started playing with halion

Now even if midi USB is unplugged, and old songs where I never used halion, still I get these alerts and no sound:

device speakers realtek high definition audio
error code FFA-8-000D [8889000a]
asio direct sound full duplex driver audio system does not seem to respond
maybe card does not support full duplex mode ok

Seems like hooking up ci-1 solved this problem but I can still only get one sound from the midi.

Are you using HALion as a plug-in in Cubase or as a standalone instrument?
If as a standalone, you have to setup the audio and MIDI inputs/outputs separately.
HTH
J.L.