You need the 128 bit pack as well as the add on.
Open both in 7zip (7-zip.org) and drag from the add-on into the main Sphax 128 pack.
Then place the combined pack into: C:\users\%username%\AppData\roaming\.techniclauncher\tekkitlite\texturepacks
http://bdcraft.net/forum/128x64x32x-tekkit-lite-smp-050-addon-pack