Swipe from the side to activate a widget overlay?
I am the developer of Bubble Cloud Widgets. I tried, and it is fully compatible with Smart Task Launcher, but you have to invoke the special "Widget Measure Mode", since STL doesn't report the widget size correctly.

Here, I shot a video for you:


https://youtu.be/UYsoU-xwqkI


This is my blog entry on this subject:


https://plus.google.com/111815032990260235809/posts/1WXHmh3V9bX