As much as I hate admitting defeat, I've been looking into it for the last few hours and I can't find anything that might make this work. For Magic Launcher, another 3rd party launcher tool, the only way to get it working is to install LiteLoader with its installer and then load the instance from the regular .minecraft folder. Unfortunately, that's not going to work with the Technic launcher at all...I think the way Liteloader is set up is just totally bananas which sucks because I'd really love to use it with a couple of lite mods.
Ugh!