I just completed a custom pack for my server on Minecraft 1.6.4 and added the bin, mods, and config files to my zip and uploaded it to my public dropbox. However, it doesn't install forge from the modpack.jar for whatever reason.
here's the link if anyone could please assist me.
http://www.technicpack.net/modpack/details/aerynthmc.346853
I'll supply some additional info,
The Dropbox zip is called modpack
Everything is lowercase in the folders/modpack.jar
I grabbed the latest 1.6.4 Forge Universal download.
I had to do extensive testing and modified config prior to adding them to the zip. If I extract mods and config from the zip it runs flawlessly on minecraft. tekkit just doesn't want to install forge.