The update functionality of the control panel and the editor is broken due to the move of YAWL from Sourceforge to Github. This affects YAWL version 3.x.
The fix of this problem will come with YAWL 4.0 which will be released soon. Everyone should update to this new version as soon as it is available.
Update problems in YAWL 4.0
I had problems also updating YAWL 4.0. The yawl contrlo pannel show the messagge failed to donwload updates with the list of link to github (see image: goo.gl/tFtTDl).
Connection is ok