I have not tested any widescreen resolutions, but it can not hurt to try. If the game crashes, you can try a lower resolution (you'll likely crash opening the automap that much higher than the supported resolutions, even if the game itself is ok).
With Beyond Divinity, the maximum supported resolution was 1280x960 (IIRC). For me, the text in books (etc) was starting to get a little small at that resolution, so I played at 1152x864.
