Quick fix, i added missing "new"
MODIFY
src/Pharo-Launcher-UI.package/PhLTitlebarModel.class/instance/initializeWidgets.st
src/Pharo-Launcher-UI.package/PhLTitlebarModel.class/instance/initializeWidgets.st
initialization
initializeWidgets
- (label := LabelModel)
+ (label := LabelModel new)
text: ''.
- (refreshButton := ButtonModel)
+ (refreshButton := ButtonModel new)
icon: Smalltalk ui icons refreshIcon;
action: refreshAction;
state: false.
\ No newline at end of file

MODIFY
src/Pharo-Launcher-UI.package/PhLTitledTreeModel.class/instance/initializeWidgets.st
src/Pharo-Launcher-UI.package/PhLTitledTreeModel.class/instance/initializeWidgets.st
initialization
initializeWidgets
- titlebar := PhLTitlebarModel.
- tree := TreeModel.
\ No newline at end of file
+ titlebar := PhLTitlebarModel new.
+ tree := TreeModel new.
\ No newline at end of file

Quick fix, i added missing "new"