Here is what I have come up with for my campaign.
The development of Wizardy, defined as the memorization and casting of spells, has two components: Scribing and Memorization.
Any adept can take the feat "Scribe" and place in a parchment the code for casting the power they can do naturally. The adept must make a fatigue check as normal for the power when scribing the scroll. When a scroll is written, the power level of the spell is fixed at the rank (no ability modifiers) of the adepting scribing the power. The adept must also succeed a wealth check equal to 10+rank of the spell.
Any adept may cast the power from the scroll, consuming the scroll. No fatigue check need be made.
Alternately, an adept with the feat "Memorize" may learn the spell placing it in his mind for casting at a later point in the day. The learning process does not consume the scroll, no must the adept make attempt when learning. However, when the adept "casts" the spell, the power is wiped from his mind and the adept must make a fatigue check as determined by the power cast. The DC of the spell cast is fixed by the rank of the scriber, but may be modified by the casters ability score.
An adept with the Wizardy fets may lear 3 spells in this way. The feat may be taken several times.
Note: Only an adept with who knows a power may scribe a spell. Having a spell learnt via the Wizardy feat does not count as "knowing" a power.