Q: Does this mean that the Increased Reflexes Spell and Improved Reflexes Adept Power work fine together with the Increase Reaction Spell and Improved Reaction Adept Power?
I don't see why they shouldn't.
(but you can't use it to exceed the +4 augmentation limit for attributes)
On the same note;
Adrenaline Boost give initiative.
Wired Reflexes and Improved Reflexes both state they can't be combined with other technological or magical increases to initiative. The description for the spell Increase Reflexes does not explicit say this.
Q: Does this mean a Mystic Adept can combine both Adrenaline Boost Adept Power and Increase Reflexes spell?
(as long as you don't exceed a total of 5d6 as this is the limit for initiative dice)
Q: Do drugs count as a Technological increase to Initiative, meaning their bonus Initiative dice do not stack with magical Initiative dice sources?
Even if "Drugs" would count as Technological" (i doubt that, unless maybe it was some sort of nanobot drug), it would still stack(*) with the Increase the Reflexes spell - as the Increase Reflexes spell seem to stack with drugs, technological and even magic (as long as the magic is not another application of the Increase Reflexes spell).
(*)as long as you don't exceed a total of 5d6 as this is the limit for initiative dice.