[ +- ] Shifting Rules
Within a limited reach, the mage does not have to bother casting formal teleport spells on themselves every time they want to shift locations. They may instead use an ability called Shifting. At level 2 and each level afterward, they gain 5 ft. onto their shift. When a 5 ft. increment is spent, that increment cannot be used again until the next day.
Activating the Shift is neither a movement phase nor an action phase. At any time in or out of battle, they may spend one or more of their 5 ft. increments to teleport their body and everything on their person, but nothing else, a very short distance. This happens between seconds, so that if they use it to avoid an attack, gain ground, or out-pace a pursuer, there is nothing that can be done to stop them. While the shift only moves them 5 ft. by default, they may use up to their full number of daily shifts in one go if desired.
Sounds like you've got the book figured out. See the Spoiler above for how Shifting works. I don't think that would be something you'd need much ritual for; more of a special power. Potions fall under Item creation (Artifice Magic) though, so no go on that one. Think about it this way, though: the book is not a power source. If you lose it, you still know how to use magic. You just don't have the book as a resource, to look at and check what you're doing.
I think your test run is about done, no need to continue in the small room. We've only got one player who's still working on their character. I think you and the others can begin final preparations to join up and be a group. I might have to work something out other than the group text document.