QuoteCould for some reason the m_registeredFonts vector be empty?That wouldn't cause any issues. If it crashes in "Backend::unregisterFont" then it means that the backend is a nullptr and accessing m_registeredFonts is invalid.
Quoteit won't load the SFML libraries because they're not signed correctlyI vaguely remember that you had to go into the macOS settings somewhere and press a button to add an exception for the unsigned library. And you had to do the whole thing once for each library (i.e. separately for sfml-system, sfml-window and sfml-graphics). But maybe there is some setting in xcode to completely disable this security.
QuoteNow I get BAD ACCESS errors from my class destructors that use TGUI. Does 1.6.1 require explicit cleanup steps that 0.6 didn't?It doesn't require explicit cleanup, but no TGUI widgets or textures are allowed to exist anymore after the backend is destroyed (which happens when calling setBackend(nullptr) or in the destructor of the Gui object if you don't manually create a backend). If TGUI objects still exist afterwards then their destructors would crash at the end of the program.
QuoteAre there any other things I need to change?None that I can think of.
QuoteIs it viable to have a Game class with `tgui::Gui gui;` and then call `gui.setTarget([RenderWindow&])` in the class constructor?Yes. You just have to be careful about which objects you put in the same class.
auto backend = std::make_shared<tgui::BackendSFML>();
backend->setFontBackend(std::make_shared<tgui::BackendFontFactoryImpl<tgui::BackendFontSFML>>());
backend->setRenderer(std::make_shared<tgui::BackendRendererSFML>());
tgui::setBackend(backend);
At the very end of your main function you would put the following line:tgui::setBackend(nullptr);