Importing multiple BVH files using MakeHumans "load and retarget" function

Hello, I’m new to Blender, so this might be extremely simple. I’m using the MakeWalk plugin to load BVH files onto my makeHuman model. It works perfectly when I do it, but when I try to retarget a second BVH file, the original gets overwrote.

How can I work with multiple BVH files?