tested its firmware on my DSTT and it works loads games too. http://www.dealextreme.com/details.dx/sku.29494 the R4/R4i pocket is the name of the cart and it's loader seems to be a hacked version of yasu menu even has his little debug screen when you touch the bottom of the screen. doesn't seem to recognise my usercheat.dat correctly either(might be my fault) don't know about "improved" compatibility over any of the hacked firmware since that's probably what it's loading from. copy the files to your sd card and rename the _DS_MENU file to TTMenu.DAT and see what i mean. on another note R4.PK is the menu it boots to though it redirects you to ysmenu so i just cut out the middle man.