I took my new Macbook Pro on a tour in Europe to process images using Lightroom 5.4 and Photoshop CC2014.
I encountered consistent problems in LIGHTROOM with the slider controls NOT releasing after I removed my finger from the trackpad. If I tried to use the trackpad to move the cursor elsewhere on screen then ONLY the slider would respond. No button-pushes (e.g. ESC) would release the slider. I took to Force-Quitting Lightroom to recover control, but lost plenty of work! I eventually found that applying some extra-pressure punches to the trackpad would often release the slider.
I accuse Lightroom of causing the problem because Photoshop did not cause such problems with its many sliders.