From the readme:

Install instructions:

- Copy the program to /PSP/GAME/UPDATE
- If you have 1.50 addon, make sure you have the kernel of game folder configured to 3.71, or the
program will not even start.


Changes:

- There was a bug that caused corruption when writing files of more than 32256 bytes using usb flash.
The bug has been corrected, and now the implementation is as reliable as it was when it was based on 1.50 kernel.
(tested with a full restauration of a dump)

- Psp Slim: a functionality to let the charge of battery when connecting a usb cable has been added.
This feature is based on Noobz plugin code.
By default is not enabled, you can enable it in recovery.
Note that the charge of battery may be delayed some seconds since the moment you plug the cable.

- After installing this update, program at /PSP/GAME/UPDATE will always be executed on 3.71 kernel, despite configuration.

- VSHMenu: vshmenu will not be executed when onscreen keyboard is active, to avoid the lost of
the select button function in the keyboard.
An option to reset the psp has been added.

- VSH plugins are not longer executed anymore in recovery mode, that was the cause of pseudo-bricks.


Note about twi bugs remaining:

The WLAN network error, and the PSP Slim psx game change of brightness.
These two bugs are copyright of Sony :) happens too in OFW.

The WLAN network happens when there is no network available, so not a big problem.