Yeah there are two OPT bugs:
http://bugzilla.mess.org/show_bug.cgi?id=1843
http://bugzilla.mess.org/show_bug.cgi?id=1847
The second one seems to be almost working now.

Current SVN seems to have a problem where vertical scrolling works OK, but horizontal scrolling is chunky (scrolls several pixels at once rather than one at a time). This can easily be seen at various points in the Chrono Trigger intro.