You have to edit the various shaders to change the flashlight parameters. I've done it myself for a previous project. Unfortunately, it's a bit tedious to edit every single shader to adjust the parameters consistently and then if TGC updates the shaders in a future release you have to fix them again for your personal project.
System Specs: OS - Windows 7 Home Premium 64-bit SP1, CPU - AMD Phenom II X4 945, 3.0Ghz, RAM - 8Gb DDR3, GFX Card - 2048MB NVIDIA GeForce GT 640, FPSC-R Version - Beta 1.0085