I have the exact same problem.
I created a Technic account just to post here and tell you that I have tried all of the above, and every single forum post and found nothing working.
Yes, I nuked and reinstalled everything, I de-activated my anti-virus, any compatibility mode won't do anything.
I just get a blank tekkit window and the technic launcher in the background. If I have to I will make a video of every single attempt to prove you I've tried everything one should try before posting.
I have Windows 7 with Comodo 2013, Minecraft vanilla works fine the problem is with the Technic pack only.
I used to play Technic pack SSP and Voltz.
I've downloaded the latest technic launcher which is Build 224,
I've increased the memory of Technic Pack,
And yes,
I tried,
Percussive maintenance.
Please help.