Watching NOD work?

I like NOD32. Very much in fact. But, after watching it do its' daily updates (I use dialup), I've gotten curious about what I see during updates. So,

1. I ususally see Update display a file named "expire.rar." I know it is not local, because I can not find it! And, I notice that it is mostly about 3KB in size. Lately this file has grown bigger (up to 124KB one day) at various times. If I get the expire.rar file from ESET, I never get any further files and NOD32 does not update. Odd, but acceptable!
What is this file, and, what does it really do?

2. What does the file named "update.ver" do? I see it less often, but see it none the less, and, usually I get nothing more from ESET.

3. Am I correct that the ESET files "engine1.nup" and "engine2.nup" are the files that new virus info is packed in for an update connection?

4. I do know that I have seen component updates come down to me even AFTER all my clients and server updated to v2.70.32. Fair enough. Yet, even with "what looks" like component update files arriving, I do NOT see any difference in my Mirror directory. Have I done something wrong?

Trust me, this is not serious. NOD32 is working so well I can only wish W2K and WinXP worked this well! LOL! A truly superb product. I am glad I purchased it.

Thank you for any info that may be shared. Not trying to peek under the hood, just wondering what might be going on because whatever is going on is going on very well so far.
Best,
Duncan

 

1. maybe infor about your nod32 expiration date
2. info about update that should be downloaded
3. yes. you are correct, its the updates
4. not you are ok