Improving dictionary support is definitely on my to do list. Also, Faterson correctly points out that to reliably switch system dictionaries, you have to install and switch keyboards. This is of course, is less than optimal. I'll will certainly look into it. However, it unlikely that it will be in DICT format. I've read in several places that there are copyright issues. Although my findings are inconclusive I don't really want to risk it.
Faterson, I'll contact you directly to investigate the hyphenation issues you're experiencing.