The two games are too different for there to be any easy way of converting them. Not saying it's impossible: both game's level formats are quite well understood. But to write a converter would take a considerable amount of time and testing, and the few people who are talented enough to do that likely don't have the time or the will to do so.

There have been a few attempts at manually converting the levels, but that is a very tedious process and as far as I know no one has done much beyond recreate one or two levels.