1.) I had a feeling the "incorrect" wouldn't be correct so I didn't save the changes.
2.) Here is how I updated my board per the following instructions-
You have no MOD's. A custom style is not a MOD, it's just a custom style.
You do not use the automatic update method for boards like yours.
With no MOD's the best way to update is to download the full 3.0.5 package, extract and upload everything except config.php, /files & /images to your server overwriting what is there. Run the /install/database_update.php and then delete the install folder as well as everything in the /cache folder except index.htm & .htaccess.
**If you have customized the default style prosilver or subsilver2, do not upload the /styles folder either, manually update those styles with the code changes package. If you have customized the defaults then uploading the /styles folder will overwrite all your style edits.
Always make a backup of your database as well as the folder you have phpbb installed in before upgrading or making any changes.
After updating you download the code changes package which lists the manual steps necessary to update a style to version 3.0.5. In your case as I mentioned much earlier in the topic, your custom style is prosilver based so you just use that file's instructions for manually updating your style.