It required some minor additions to the engine code, but nothing too brutal.
instant_resolve = "last" now runs last resolvers as well;
generic and genericlast resolvers now receive additional arguments
that are passed to resolvers.

Disabled the animated background on the main menu, it was always lagging behind in terms of prettiness
New FontPackages engine class, lets easily define and switch "themes" of fonts
Switched to a new default font, the previous one is still available in the GameOptions as the "web" one

Added in some callbacks and stuff.

instance of it.

New hook "Boot:loadBackground"
Addons can add a new splashscreen by having a special boot-screen folder

Doesn't handle multiple slots terribly well.