TWEWY freezing depends on both the fact that the M3Real just can't run it quite right, and the fact that your MicroSD may be too slow.
There have been a lot of problem reports on this particular issue, with the TWEWY movie freezing on M3Real flash cards.
For example, here's a topic a while back about this problem:

http://gbatemp.net/index.php?showtopic=918...p;#entry1234227

Apparently the fix is to open and close the DS lid during the movie, or just using an emulator to watch the movie then restore the post-movie save to the M3Real.


As for Pokemon Platinum, the save is 1024KB as opposed to the normal 512KB (this is because Platinum allows you to record battles, so a larger save type is needed). This is why it doesn't save properly, but I assume the M3 team will release a firmware update to fix this soon.

 

The fact that both games have issues could be down to the particular firmware you're running, or the Micro SD. You could try a few different things in order to get both working, which are:

- Try formatting the SD card. Sometimes when games have errors or do not function correctly, this is normally one of the best fixes in order to get them up and running.

- Delete the current version of the firmware you are running, and replace it with a newer version (if any), or use a freshly downloaded version of the same firmware edition. This used to happen a lot with my M3 Real and my R4DS, and normally this solution would work. Alternatively, you could try using the M3 Sakura firmware if you aren't already. That should play both Pokemon Platinum and The World Ends With You perfectly, because I know they both work without any hitches for me on that firmware.

Anyways, I'm hoping one of those ideas will work for you. Good luck and I hope they load properly. ^^

 

might be usefull to tell us more about your microSD,
what size, brand, class, and factory location.(all this info can be found on the microSD itself)

example: i have a 4GB sandisk C2 from china(SDHC) (which works fine with twewy btw.)