If you know how to script a little, you can use TextRectangle() to bump the mud-output up a number of pixels so you can hover the Infobar where you want it. Or you can skip the infobar alltogether and just move straight to a miniwindow to draw at the position in question.
What version do you have? Miniwindows are a rather recent addition - I'd update to version 4.37 if you haven't. A lot of bugs with them have been fixed in that version.
It may not show on the main download page since Nick is kind of conservative with introducing new features to all users of MUSHclient while there may be bugs remaining. But I have used miniwindows for over 3-4 months now and can pretty much garantuee there is nothing that will make it crash or really bugs it out. There's some minor problems, but they'll get fixed in due time. Look in the Announcements forum for the link.