Your plugin allow to append HTML in the last elem of the Json in the baloon_text
.
{"latitude": "31.42", "longitude":"-98.61", "icon": "i.png", "baloon_text": ''}
So you can append your own HTML content for each marker. Based on this, you just have to reproduce what you want, and in this case the old Google Maps InfoWindow.
I've got some time, so I've made a Fiddle almost same I think, all you have to do is to play with CSS
according to what you want to show exactly :)