I just tried to do a fresh installation of the latest v3 and everything seemed to go ok. I got to the admin screen and clicked the Global Settings button to change password etc.
After making a few changes, I clicked save and got the following error:
The asset "/Users/username/limesurvey/assets//styles-admin/Apple_Blossom/images/logo_icon.png" to be published does not exist.
I noticed that there was a double slash after the assets part of the url - could this be the problem?
I looked in this directory and there was no file called logo_icon.png. None of the other admin styles had this file either.