Ableton Live has always been a pain for automating external gear especially outside of the midi clips in the arrangement section. Though there's not much to control via midi for the Minibrute. I made a quick max4live midi plugin to control pitch bend, mod wheel, and after touch. I even added a nice panic button in case there's ever a stuck note as sometimes is the case with hardware. Have fun automating.
http://www.maxforlive.com/library/device/1830/minibrute-control*edit - grab the patch from the link as it's better to keep it in one location instead of different versions spread across the net.
*edit 2 - This plugin has morphed into my Keyboard Control. It should give access to most of automation and settings missing in Ableton live and/or push for any hardware synth.
http://www.maxforlive.com/library/device/1946/keyboard-control*EDIT 3 - ***UPDATE 2.0*** Now includes access to all the parameters found in the editor. Firmware 1.0.3 required. (I sold my Minibrute a while ago, waited too long for this firmware sorry. so if this doesn't work 100% feel free to send me a minibrute to test it out). Good luck.