Add ReverbNation's HTML5 widgets to your WordPress with versatile shortcodes, visual editor button, and several customization options.
This plugin only supports the HTML5 widgets, so there's no option to create Flash-based widgets on-board.
No, sorry; the goal is to stick with the HTML5 widgets only. The code can be adapted, though, if you have the the motivation.
ReverbNation has not made this option available at this time.
There is no limit to how many widgets you can place on a page.
ReverbNation does not actually offer a widget that automatically refreshes with only the artist's latest single; this is an illusion created by the Reverberation plugin. It does indeed create the artist's full playlist just like an allsongs widget would do but it's only tall enough to show the first song. Obviously, if the height is adjusted, the illusion is broken. For this reason, the height attribute was disabled for this widget.
No, sorry. Here's a metaphor to help put it in perspective. Think of WordPress like a cool, new bike and think of those who run the .com site like your parents. Now, think of this plugin like a big ol' jump that you want to take your bike over. Sounds fun, right!? Thing is, your parents have put training wheels on your bike, so you'll only be able to watch at the sidelines for now. Ok, not a perfect metaphor, but I think it communicates the idea. Again, sorry for this, but I'm powerless to help you out in this case.
There's been RN plugins for several years and none of them got in, so there's no reason to expect this one will be any different. There was a time when you could make a request for plugin inclusion on the WP.com site, but they've (at least as of this writing) blocked off their contact form from everyone who is not a paid member.