Updated first post with Condemned Tower.
Well, that one didn't take long *except* for the background of the tower. The original one is a 3D model that I couldn't extract from the ROM, much less reproduce in Cinema4D, so I just did my best and spent about a few hours manually distorting the graphics, first by resizing the tiles horizontally by hand, and then vertically one pixel column at a time to achieve the final effect. Paint Shop Pro 8 unfortunately had nothing to achieve the desired distortion so I was kind of stuck. However, I might be able to get my hand on a recent version of Photoshop soon so maybe I won't have to suffer like that too much in the near future.
Please all note that the maps posted are nowhere near final, as they are missing several effects such as light halos around candles and in the case of the Condemned Tower map, clouds in the sky. I just have to find a way to reproduce the same effect as in the game which is pretty tough considering all the parameters 3D textures seem to have on the DS (going by the 3D Viewer for no$gba, there are several parameters named Spe, Dif, Amb, Emi, Light0 to Light3, Shin, Edge, Toon & Fog). And I haven't a clue what any of that means in practice.