There was a little bug that crept into the last few BumpTop releases with our automatic updater. If you have an existing version you will likely need to re-download the update directly from the BumpTop beta website using your invite code. http://bumptop.com/download Or you can use the workaround described below.
If you've lost your invite code just email feedback@bumptop.com to re-request it.
WORKAROUND
The built-in Updater will fail if you allowed BumpTop to submit anonymous usage statistics when you installed it. When it detects an update (0.1.1197) and you say "Yes" you want to update it will bring up a window asking you if you want to submit a screenshot of your desktop. The problem is this window is positioned off screen and you can't actually click yes. If you just select it from the taskbar and hit enter it will proceed to download the update without uploading a screenshot.
Sorry for the inconvenience, the problem is now fixed. The new update has many fixes Thanks to your crash reports and feedback. We've also added the much requested ability to intuitively drag out of piles without using the Pie menu.