Fortunately, evil/good/savage settings have no effect on the rest of worldgen, so you can easily just tack them on to an otherwise-gennable world. So all you really need to do is tweak the temperature ranges to be low and you should get freezing biomes. Try in the 0-10 range. Just be aware that if you make the entire map into a glacier, then humans and elves won't be able to exist, which may cause map rejects (it's fine if they die out during history; I don't know if it's OK for them not to be able to exist ever).
You can make magma more likely by increasing the volcanism on your map, and by increasing the number of volcanoes. These are two separate things; the former generally affects the frequency of magma pipes and the likelihood that rock layers will be igneous, while the latter creates 3x3 regions of mountains with a big magma pipe in the middle, and scatters other magma sources about the vicinity.
Underground rivers and HFS are both mountain features, and will exist in any mountainous region as long as the mountain isn't too tiny (As near as I can tell, the game places the HFS, then bottomless pit, then chasm, then underground river/pool, so if you run out of mountain prematurely, you won't get the underground water). You can improve your odds of getting both the river and the HFS by making lots of very small mountains, which forces the mountain features to be closer together. Mountains are any region where the elevation is 300 or higher, so by tweaking the elevation to be in the 290-300 range with very high deviance, you can make tons of small mountains. Note that these settings preclude both oceans and mountain peaks, so you'll have to set the desired numbers of those to 0. Otherwise the maps will continually get rejected.
Finally for evil regions, just set the desired number of evil squares up. 400 for each of the 3 settings seems to work decently for a 65x65 map. You can also do this for savagery to make a "more evil" setting.