Picasa Widget works as a widget, making very easy for you to embed in sidebars (if supports widgets) the latest albums from your Picasa account, or th
Yes, each Picasa Web Album have a configurable thumbnail (on Picasa website). This can be used to show your last n albums.
Yes, you can from the last album or from the last n albums (you choose).
Well, you have some options. It depends a lot on the size of your sidebar. You can have one column or many. And you choose how many pictures.
Yes, you have some options in the admin are of this plugin. And you can also use CSS.
This plugin use Picasa API and Picasa API use some standard sizes. Some are automaticaly squared, other not. We have to use those sizes.
No. See Thoughts of a codes solution.