The 1031_gm_portal_challenge_package.zip file you have requested: Garry's Mod / Add-ons / Half-Life 2: Garry's Mod Portal Mini-Mod - 3.98mb is not available. Perhaps try browsing all files for the game Half-Life 2 and upload any files you want to share or are missing. This is the only information we could locate:
Well you all wanted it...we have portal! (Not the final and complete stuff) DaMaN at the gmod forums has created this mini-mod for Gmod. It has the cool little portal gun and custom made challenges, most of the stuff seen from the videos and more. This is an amazing little add-on for gmod and all of the stuff you need comes in this package. Enjoy :D
Welcome to the Aperture Science Enrichment Center. Let's look at some of the challenges you'll face as a test participant:You may be required to perform simple tasks, such as locating an exit. These simple tasks may be supplimented with insurmountable obstacles.