It seems I am no longer able to just 'edit' a pack. Only the option 'edit with form' is available, but I don't want to use the form...
EDIT: It seems that the option does appear in the menu for some of my packs (e.g.: Guide to run REGS with SRLE on Medium Systems), but for other packs that I worked on the option to edit does not appear from the 'page tools' menu.
Also after creating a new pack the option doesn't appear.