here are the some of latest firmware for your MP4/MP5 (hang on start , white screen )

1).280_V13 090818 slide type

Board id : 280_V13 090818 slide type
LCD: slide type
Chip : MM spmp3054A
Cam : 767A0901 0903
http://www.4shared.com/file/203266622/f4ade660/280_V13_slide_3054a_by_rp_yone.html

2).M2-PL28-2052-V2.0

Board id : M2-PL28-2052-V2.0
LCD: SXD0018
Chip : MM spmp3054A
Cam : 0307A0900W
http://www.4shared.com/file/195757185/7faa131e/M2_PL28-2052-v20_board-spmp305.html

3).a261_v2_090829

Board id : a261_v2_090829
LCD: Ls 2255a
Chip : Spmp3054a hl171
Cam : Xhb 7678f
http://www.4shared.com/file/173507067/fd973cf8/a261_v2_090829_by_rp_yonex.html

Board id : M6A-PL25-3055-YD503-MAIN-V60
LCD:
Chip : MM spmp3055A
Cam :
http://www.4shared.com/file/204167209/adcfdef3/250_v15_2gb_3055a_by_rp_yonex.html