as you already did the PRS+ base installation, you really should try Analogus ZORK- version.
It is far ahead the code-state from 2.1.01a and adds some very nice font-fine-tuning direct in the Size-Overlay. The menu you get when you push the size-button.
For the more tech-savvy: mentioned features are also included in current PRS+ standard-repository. But you will have to buid your own installer.
The Zork looks great.... I think I Russified my current dying 350, the Boroda version - to enable different epub fonts.
Zork looks as easy or easier with better options... thanks!