Making Qsys Components and Fixing Memory Problem

You can't change it, but you don't need to.

You only need to implement 16bit access in the complete way. As I wrote above, the sample component in the tutorial only implements a minimal interface, without taking into account all 4 byte enable lines.

So, if you want 2 16bit registers at memory addresses 0 and 2 (please note we are still using byte addressing) you access the first one when addr=0

and only byteenable lines 0 and 1 are asserted; the second one shall be accessed when addr=0 with byteenable 2 and 3 asserted.