MediumGauge has just rolled out an update for his awesome PSP Filer application. Looking from the translated changelog we see that various bug fixes have been applied. And some changes to the picture viewer.

This application lets you, dump UMD’s to your memory card in ISO format, extract 7-zip, WinRaR and Zip archives. Plus Copy, Paste, Move files and lots more. A must for any Custom Firmware enabled PSP.

PSP Filer 6.6 Changelog (Translated from Japanese)

version 6.6:
○ filer
· 2G bugs were not properly calculate the directory size exceeds the byte
Fixed.
○ Audio Player
When there is no audio to play, the ↑ Fixed a bug where pressing down.
· UMD Fixed a bug that fell on the drive is started.
Mode, add a background.
Add functionality, display of character code conversion of a string tag.
, Added the ability to display the playback time.
Long tag, to display the ticker.
○ image viewer
· ○ + □ mark image files / added the ability to remove marks.
(Image in the archive is not marked)

(Reprinted from following readme)
Folder.jpg folder if it found the first Without jpg
A file and view it as a cover image.
Background operation mode and the audio player is started,
The following changes in behavior by the state.
1) When the file operation was started from the menu: former player without
Show.
2) mp3 or wav files on the file when pushed ○: Play the previous
Yeah it is discarded, the audio file is played under the cursor.
Note: background operation, CPU load increases and audio playback of
May want to pause.

Source: MediumGauge (JP)