Upgradeing a published website using ftp. Many questions

[Cal Who]

I published my website using vs2010.
I checked the box that made it upgradeable.

As a check I ftp copied default.aspx and default.aspx.vb to the site
replacing the published files.

Looks like it still works.

So I can update the site files using ftp?



I noticed there is no App_Code folder.

Suppose I need to update something in that folder, can I? How?


I also noticed there is a file: PrecompiledApp.config

Might I ever want to delete that file?

What is it for?


Would it make sense to delete all the files and ftp the entire site to the
host. Can a site be uploaded that way? Is there a down side to uploading
that way?


The host had generated a Blog virtual folder that got deleted when I
published. can I just create a new folder called Blog or is there something
that can only be done by the host?


Thanks in advance for any answers