Publish subscribe in Integration server 6

Hi All
We are using the publish/subscribe for ours integration. We are publishing locally and have a trigger attach to that document and execute one service. In that service we are having one jdbc service. We are not using any broker.
I have few doubts
1.Do I need to do anything special for my publishable document properties to save it to somewhere?
2. I can see some files in the document store like TriggerStorelog0000000, TriggerStoredata0000000. How can I see this data?
3.Is it right that the in case of transient error the trigger retry parameter will grab that publishable document from the document store and try to submit it again till the max retry reach?
4.What would be the nice way to deal with a situation in which if triggered service fail because of database down problem should try to send this document again to that service for 2-3 hours.
5.What should we do to not loose any document if the database is down for around 6 hours.

I know I am asking a lot but hope expert will give their prompt reply to it.