Issue solved on Win98SE, the MIDI editor opens fine with the new version 2.58 of Reaper ("fixes Win9x compatibility"). Thanks for fixing! If we now could also get the realtime MIDI-through implemented, I'd be in MIDI heaven. :)
That window placement setting thing brings something to mind. When I switched from two monitors back to one I neglected to open all the apps I use like Vegas etc and make sure that all of the windows were visible in the single monitor workspace. Big trouble for the ones that wrote their last position to a config file. A "Make all Windows Visible" (move any open window inside the current monitor space so the user can touch it with the mouse) function should be a standard thing in all apps for those kinds of situations. I've even had an errant mouse "throw" a window out of reach from time to time. Not sure how it's possible with the mouse being restricted to the monitor border but it happened. Seems like a no brainer huh? Or is "tile" suppose to accomplish that?