I also have issues, here is the error:
[11:12:34] [sEVERE] Extracted \temp\z-tekkitlite-configs-v0.5.2.zip to \tekkitlite
[11:12:34] [sEVERE] Downloading 'https://www.dropbox.com/s/1jmvt9lijtlomf8/CustomPck.zip'
[11:12:43] [sEVERE] Downloaded '\temp\custom.zip'
[11:12:43] [sEVERE] Extracting \temp\custom.zip to \tekkitlite
[11:12:43] [sEVERE] An error occurred while extracting \temp\custom.zip
[11:12:43] [sEVERE] net.lingala.zip4j.exception.ZipException: zip headers not found. probably not a zip file
[11:12:43] [sEVERE] at net.lingala.zip4j.core.HeaderReader.readEndOfCentralDirectoryRecord(HeaderReader.java:122)
[11:12:43] [sEVERE] at net.lingala.zip4j.core.HeaderReader.readAllHeaders(HeaderReader.java:78)
[11:12:43] [sEVERE] at net.lingala.zip4j.core.ZipFile.readZipInfo(ZipFile.java:425)
[11:12:43] [sEVERE] at net.lingala.zip4j.core.ZipFile.extractAll(ZipFile.java:475)
[11:12:43] [sEVERE] at net.lingala.zip4j.core.ZipFile.extractAll(ZipFile.java:451)
[11:12:43] [sEVERE] at org.spoutcraft.launcher.GameUpdater.extractCompressedFile(GameUpdater.java:249)
[11:12:43] [sEVERE] at org.spoutcraft.launcher.modpacks.ModPackUpdater.extractCustomZip(ModPackUpdater.java:103)
[11:12:43] [sEVERE] at org.spoutcraft.launcher.modpacks.ModPackUpdater.updateModPackMods(ModPackUpdater.java:86)
[11:12:43] [sEVERE] at org.spoutcraft.launcher.gui.LoginForm$3.doInBackground(LoginForm.java:831)
[11:12:43] [sEVERE] at org.spoutcraft.launcher.gui.LoginForm$3.doInBackground(LoginForm.java:807)
[11:12:43] [sEVERE] at javax.swing.SwingWorker$1.call(Unknown Source)
[11:12:43] [sEVERE] at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
[11:12:43] [sEVERE] at java.util.concurrent.FutureTask.run(Unknown Source)
[11:12:43] [sEVERE] at javax.swing.SwingWorker.run(Unknown Source)
[11:12:43] [sEVERE] at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
[11:12:43] [sEVERE] at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
[11:12:43] [sEVERE] at java.lang.Thread.run(Unknown Source)
[11:12:46] [sEVERE] Loading Launcher from 'techniclauncher/tekkitlite'
It's the relevant part from the technic launcher logs, and I'm running OSX 10.7.4
I don't get it because it does seems to be a .zip
[18:47:18] [sEVERE]Launcher is starting....
[18:47:18] [sEVERE]Launcher Build: '1.0.2.5'
[18:47:18] [sEVERE]Allocated 989.875 Mb of RAM
[18:47:18] [sEVERE]Java VM: '1.7.0_09-b05'
[18:47:18] [sEVERE]OS Version: '6.1'
[18:47:18] [sEVERE]Is 64-bit: 'false'