TM through airdisk using filevault

Ok, I need to keep my files encrypted because i travel a lot. I also want to benefit from TM's backup facility so I set it up to backup to an external drive connected to my fast ethernet AEBS.
Backup works in that it updates to the sparsebundle file that has been created on the external hard drive. What I want to know is the following:

1. Is it normal that I dont have the automatic backup feature with this setup? To backup I need to request it manually!
2. I read somewhere that in order to do a FV backup, I need to log off. I noticed, however, that it backs up even when I am not logged off! I am not sure if it is backing up FV content, but it certainly seems like it is backing up something. Do I need to log off to backup FV content or does it work when I am logged on?
3. I notice in the TM interface that snapshots of the past are available, but when I click on the FV content it is presented as a sparsebundle file. How can I access it?

Thanx for your help.

 

Bump. Anyone?