I think your method comes in very handy for those who use more than one computer. You may even run the programs from an usb stick, I think.
Not shure if I understand all what you've written. Also, I'm no specialist at AAD, I'm almost a noob but I'll do my best.
@1: The source scripts which I prefere are: Amazon.com, Coveralia, GoogleImage; which i've set to "search first" and limited to 5 results. I've checkmarked a few others too which will be asked by clicking "Expand Search" - when the first run gives no sufficient results.
I don't use discogs and have not tested it yet. In the AAD forum is a fixed version: click
@2: As I said in the tut
I guess that your settings are not proper and therefor you get a file with this name "% album.jpg".
I'd suggest you start from the beginning of the tut and follow exactly the single steps. I wrote this tut about one year ago. This setup works for me since then and I never had to change anything, so today I'm no longer into the matter and not shure what the placeholders mean and how they have to be used exactly. This is a bit complex.
@3: Not shure what you mean at this. The tut gives you three choices (=Tools) resulting in three different .jpg files. You can have more when you set up more tools in the way the tut subscribes.
@4: As far as I can see you missed the quotation mark at the end of the line:
Try to put one there or copy and paste the complete line.
The name of the "Action Group" is up to you, name it as you like it. The format string for the action is fine.
Not shure if I got your last statement right. When you setup AAD like in the tut the images are saved in the same directory/folder as the mp3 files. No need to set a path in the options of AAD - as I said above. You may move the images later in another folder or, when they have been stored in the mp3s, you may delete them. (You can always extract the images out of the mp3s later, if you need them.)
My first impression after reading your post was that it seems to me that you've mixed things up.
The "Tools" you set up by the tut are starting the AAD and doing the search.
The "Actions" grab the images which have been saved and store them into the mp3s.
Another idea would be to take a look in the AAD forums or the AAD Wiki