UCX Collision Creator
This script allows you to make an Unreal UCX collision hull from your selection in one click.
To install and use the script, do the following.
1: Drag the script from the download location to the 3Ds Max Viewport.
2: Under the Customize menu, open the Customize user interface.
3: Navigate to the Quads menu.
4: Under the Category menu find the Unreal Tools category.
5: Move the Make a single UCX Collision Box to a Quad Menu of your choosing.
5B: You could also assign the script to a "Hot Key".
6: Make sure your object is in edit poly mode and that you have at least 3 faces selected.
7: Run the script and you should now have a collision box that is the size of your selection.
I have only been able to test this script out with 3Ds Max 2010 and 2012 but the script is pretty simple so you should not have any issues using it in other versions of Max.