I have the exact same problem. Right now I'm currently using windows 7.
I've checked the logs and console, in the console the error I have is " Could not find or load main class net.technicpack.legacywrapper.launch "
And in the logs it tells me that it's likely there is a corrupted .jar in the mods directory, this error occurring while the mod is loading.
I of course have no way to fix it, as I'm not much of a technical genius. However, if the staff hasn't been notified already, this might be a good thing to tell them.