Voici ce que dit le site Wiki sur les compatibilités du DS-X:
DSX compatibility list - Scorpei.com - Wiki
0735 Castlevania: Portrait of Ruin (U) (Xenophobia) 1.1.0 Random freezes entering/inside menu. Watch for the problems seen in the JPN release. Freezes when using the teleporters in the main castle. Teleporting in each painting is fine. Oh well, looks like freezing still happens on occasion with the 1.1.0 FW.
0881 Castlevania: Portrait Of Ruin (E) (Supremacy) 1.1.0 No saving trouble, for now... edit : same problems as us version and jap version
spoiler : when you talk to Wind for missions, game precisely when you have not finished all the mission you have signed for