I am glad that you appreciate my update. In fact I just released another update. This fixes screen corruption on real hardware. Make sure you download 1.03. The update is pending acceptance in archives.

Sorry for the double post but I have updated my program. My update addresses crashing the calculator. Now it searches for the Save/load VRAM address and finds where it really is. The address is different depending on firmware versions. The download link is the same.

Yes the player does have a gui. See the attachment if you want to see what it looks like. Also I see nothing wrong with command line. Even though it is not necessary for my program I don't see any reason to avoid learning it.

This is more of a front-end to libmpeg2
The source code can be found at https://github.com/ComputerNerd/Casio-prizm-mpeg2-player
You can download the file here http://www.casiopeia.net/forum/downloads.php?view=detail&df_id=146
The latest version is 1.031 which fixes a scaling bug that causes some pixels to be ignored.
Version 1.3 fixed an issue on real hardware where the screen would get corrupt. It is highly recommend that you run the latest version. Running 1.2 or older is a bad choice.
To use this program you will see a file browser
I have it set to show *.m2v files because there is no audio but it may play mpeg2 with audio (untested) but it will be ignored
As for what resolution you should make the video I would not go over half of screen resolution it should support 384x216 maximum but malloc errors are encountered
While the video is playing press exit to go back to the file browser if you want to do such.
In the readme I have included compiling instructions if you are interested in using libmpeg2 in one of your own projects.
To encode video I used
the following avisynth script
AviSource("FILE PATH HERE")
BilinearResize(176,96)
ChangeFPS(128,13)
AssumeFPS("ntsc_video")
ConvertToYV12()

To encode the video I used HC encoder http://hank315.nl/

There are some settings that you should be aware of please use 1:1 ratio for pixels
Also if you want height to be a multiple of 16 instead of 32 make sure progress sequence is checked (In settings 2)

Icon from http://www.pubzi.com/f/Movie-icon.svg

I was wondering is there a way to get a more precise tick count than 128 ticks per second on the casio prizm? I have no idea if such an option exists or even what to look for. It appears that 128 ticks per second is the best the RTC can do. If anyone has knowledge of a way to get a more precise tick count than please do tell.

Alright I made a new release there are some slight changes but the main one is the fonts now show up
(This post was in reference to version 1.01)

Yes sometimes exiting seems to have issues occasionally not sure why I will try to fix it at some point in time.

Ignore the long list like I have said there are multiple versions of jazz jackrabbit you have most likely downloaded the shareware version. I have tested the shareware version and it works just fine.