Whenever I try to start a new game, it crashes with the following message:

Error while running event level::on_tick (ID 0)
...aming/Factorio/temp/currently-playing/puzzletory-gui.lua:87: attempt to index global 'mod_gui' (a nil value)
stack traceback:
...aming/Factorio/temp/currently-playing/puzzletory-gui.lua:87: in function 'render_basic_buttons'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:942: in function 'go_to_building_phase'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:78: in function 'init_level'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:95: in function 'handle_first_init'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:1044: in function 'handle_tick_event'
...Data/Roaming/Factorio/temp/currently-playing/control.lua:5: in function <...Data/Roaming/Factorio/temp/currently-playing/control.lua:4>

It probably broke after 1.1 Factorio release. I will try to fix it.

Done. I fixed it and migrated Puzzletory to Factorio 1.1 release. Thanks for reporting the issue.