I encounter a strange behavior with modelines on my Nanao Ms9-29.
In Vmmaker.ini, with the default monitor_spec0, and in mame.ini, specifying arcade_15 as monitor, i get all my resolutions perfectly centered (horizontally of course).
If i change monitor_spec0 with the new preset for my Nanao, and set monitor line as ms929, my resolutions are no longer centered.... So i get back with generic presets...
Am i the only one with this "issue" ?