adding light table to transform tool

This may be a ridiculously simple question, but how can I use the light table feature when I transforming a layer? I have an animation where several drawings are being transformed at the same time, and every time I go the transform tool, the light table is visually disabled (despite being checked in the drop down menu) and all the layers are at full opacity. In every other way the light table is working perfectly.

Thanks for your help!