You should create hex for CE devices. Use romtohex -p 29 bmp_name hex_name 

What are the dimensions of the image? Do you rename it to hex? Is there a version on the device already? Could you provide step by step instructions for my customer?

In Paint, go to Image/Attribute, then you see 9190w65HenSC000.bmp is 240(w) x296 (h) pixels. Keep the original size, modify the image, then save it without modifying the size. 

Hi Hiro, Unfortunately there is no BMP included in the CE package. Does the customer need to download the WM65 package to change his splash screen on a CE device?

I think it’s a standard bitmap. Open one with Paint, make changes and then save it (in the same format). Then update device via UL…