I couldn't find this information anywhere else but managed to figure it out myself and wanted to share it. In my case i wanted an "Select all" Check Box that selects/deselects all the checkboxes in a Check Box List.
How to check multiple checkboxes in a Check Box List:
Use a Transfer data action and use ";" (semicolon) to separate each value:
How to uncheck all checkboxes in a Check Box List:
Use the View's Clear method twice in a row. If only using one Clear method then the Check Box List will still "keep/remember" which checkboxes were checked even though it visually looks like it got cleared:
Both Clear's (configure) is set to only clear the cblMyCheckBoxList:
