Just like I said. Copy and merge files. Merge is an option on Vista on which we did upgrade.

So, to do upgrade, you must only copy files from 4.5 upgrade zip into the dnn installation directory you want to upgrade. Select all files in zip and copy it. Check to overwrite with new files.

Also, before make a backup. I tested downgrade from 4.5 to 4.4.1 by just copying all files from backup directory to dnn 4.5 and works fine.

Yes, it includes.

please use new release.config as template for your web.config, transferring both database connection strings. both machine keys, code subdirectories, objectqualifier and databaseowner from previous web.config. I usually use WinMerge to copare both files.