>>533
おおまかにこんな感じ
細かいとこは適当にいじって

タイプ: JScript
オプション:
const FV = GetFolderView(), a = FV.Items(SVGIO_ALLVIEW), s = FV.Items(SVGIO_SELECTION), ar1 = [], ar2 = [];
for(var i = 0; i < a.Count; i++) !IsFolderEx(a.Item(i)) && ar1.push(a.Item(i));
for(var i = 0; i < s.Count; i++) !IsFolderEx(s.Item(i)) && ar2.push(s.Item(i));
const ar3 = ar1.filter(function(c){ return ar2.map(function(c){ return c.name }).indexOf(c.name) < 0 });
FV.SelectItem(null, SVSI_DESELECTOTHERS);
ar3.forEach(function(c){ FV.SelectItem(c, SVSI_SELECT) });