The reason that no other homescreen-replacement app has incorporated HTC Sense-widgets, is because it's impossible to do.
I hope this answers your question as well.
but like i say on the mail ive sent you, it would be cool if you take the same idea of that widget, like it does launcherPro the scrolable widget of social network, sms, and specialy gmail are the most prefered things. thats why most of people are looking for sense kind of launcher.
i wana belive that he want to say this, htc sense widget are only for rosie launcher, and rosie launcher is very complicated.
a video of the wonderweel it would be soooooooooooo SWEET!
just like the first day, im going to keep loking at this project.