had same problem with a few games dstt/dstti not getting regular firmware updates, i switched to an acekard 2i with akaio 1.6 all games work at present www.ndscardshop.co.uk. you can even connect ds to wii for pokemon trading.
still have the dstt and dstti may prove handy sometime in the future, i was surprised how good the acekard 2i is.
Just checked, no errcode:- 4 using new DSTT 1.17a12 rev05, but still white screen.
We're advancing, slowly, but surely, towards getting it to work.
For the moment, use NO$GBA 2.6a (It's an NDS emulator for PC, to all u noobs out there). It works
was a die hard dstt/i user still got it but use acekard 2i akaio 1.6r2 and all the games that have problems on dstt/i are solved the ackkard will allow firmware updates for loaders cheats wifi plugin and save.bin through the ds online.
also things line wiipokemon battle revolution and other games that allow the ds version of the game to connect to the wii if you start game and hold X button they connect instead of 2 white screens.
dstt firmware official or not are good but are a few months behind other cards no including N5 or and R4 series
alternative skins put in TTMENU/SKIN folder extract the downloaded skin to a folder and put it next to default folder don't delete default folder and you can change it via ds on the flyhttp://www.ndsthemes.com/themes/title/dstt
makes the dstt/i very cool will go back to it when they start updating it more regular
