diff --git a/ui (gen4)/features/filesystem.js b/ui (gen4)/features/filesystem.js
index 381ce423..2c55e867 100755
--- a/ui (gen4)/features/filesystem.js	
+++ b/ui (gen4)/features/filesystem.js	
@@ -1603,6 +1603,7 @@ var FileSystemWriterActions = actions.Actions({
 		'export-preview-size': 1000,
 
 		'export-preview-size-limits': [
+			'no limit',
 			'900',
 			'1000',
 			'1280',
@@ -1707,9 +1708,12 @@ var FileSystemWriterActions = actions.Actions({
 
 	// Export current state as a full loadable index
 	//
+	//
+	// NOTE: if max_size is given the base image in the target path will
+	// 		be replaced with the largest preview under max_size.
+	//
 	// XXX resolve env variables in path...
 	// XXX what should happen if no path is given???
-	// XXX add preview selection...
 	// XXX handle .image.path and other stack files...
 	// XXX local collections???
 	exportIndex: ['- File/Export/Export index',
@@ -1723,6 +1727,7 @@ var FileSystemWriterActions = actions.Actions({
 			include_orig = include_orig || true
 
 			// XXX is this correct???
+			// 		...get this from config...
 			path = path || './exported'
 			path = util.normalizePath(path)
 
@@ -1830,29 +1835,45 @@ var FileSystemWriterActions = actions.Actions({
 
 				if(previews || img.path){
 					var seen = new Set()
+					var max
+					var replace_orig = false
 					Object.keys(previews || {})
 						// limit preview size...
 						// NOTE: also remove the preview resolution if 
 						// 		it's smaller...
-						// XXX if we are limiting preview size then we 
-						// 		need to also update .path to the correct
-						// 		preview size (use a preview as source)
 						.filter(function(res){ 
 							// no size limit or match...
 							if(!max_size || parseInt(res) <= max_size){
+								// get the biggest remaining preview...
+								max = max == null || parseInt(res) > parseInt(max) ?
+									res
+									: max
 								return true
+							}
 
 							// skip and remove...
-							} else {
-								delete previews[res]
-								return false
-							}
+							replace_orig = true
 						})
 						// get paths...
-						.map(function(res){ return decodeURI(previews[res]) })
-						// XXX might be a good idea to include the max 
-						// 		preview if hires is too large...
-						.concat(include_orig && img.path ? [[from_path, img.path]] : [])
+						.map(function(res){ 
+							return res != max ?
+								decodeURI(previews[res]) 
+								// NOTE: we will skip including the preview 
+								// 		we are using as the primary image to
+								// 		save space...
+								: null })
+						// add primary image...
+						.concat(include_orig && img.path ? 
+							[[
+								(replace_orig && max != null) ? 
+									// replace the base image with the 
+									// largest available preview...
+									previews[max]
+									: from_path, 
+								img.path
+							]] 
+							: null)
+						// build the from/to paths...
 						.forEach(function(preview_path){
 							var to
 							if(preview_path == null){
@@ -2402,7 +2423,8 @@ var FileSystemWriterUIActions = actions.Actions({
 					function(){ 
 						return actions.config['export-preview-size-limit'] || 'no limit' }],
 					{ buttons: [
-						['&times;', function(p){
+						//['&times;', function(p){
+						['clear', function(p){
 							actions.config['export-preview-size-limit'] = 'no limit'
 							parent.update()
 						}],
@@ -2414,7 +2436,18 @@ var FileSystemWriterUIActions = actions.Actions({
 						'export-preview-size-limit',
 						{
 							length_limit: 10,
-							sort: function(a, b){ return parseInt(a) - parseInt(b) },
+							// sort ascending + keep 'no limit' at top...
+							sort: function(a, b){ 
+								return a == 'no limit' ?
+										-1
+									: b == 'no limit' ?
+										1
+									: parseInt(a) - parseInt(b) },
+							check: function(e){
+								return e == 'no limit' 
+									|| !!parseInt(e) },
+							remove: function(e){
+								return e != 'no limit' },
 						}))
 		},
 		// XXX BUG: history closing errors -- non-critical...
diff --git a/ui (gen4)/lib/widget/browse.js b/ui (gen4)/lib/widget/browse.js
index 626e3421..7516246a 100755
--- a/ui (gen4)/lib/widget/browse.js	
+++ b/ui (gen4)/lib/widget/browse.js	
@@ -644,6 +644,9 @@ function(data, options){
 // 		// list length limit is reached...
 // 		overflow: function(selected){ ... },
 //
+// 		// predicate to test if an item is to be removed...
+// 		remove: null | function(item){ ... },
+//
 // 		// list of items to remove, if not given this will be maintained 
 // 		// internally
 // 		to_remove: null | <list>,
@@ -731,6 +734,8 @@ function(data, options){
 // 		properly...
 // XXX the problem with this is that it adds elements live while removing
 // 		elements on close, either both should be live or both on close...
+// XXX can we avoid creating the remove button on items that do not pass
+// 		the options.remove(..) predicate???
 Items.EditableList =
 function(list, options){
 	var make = this
@@ -1141,7 +1146,7 @@ function(list, options){
 				function(){ $(this).trigger('itemedit') })
 	}
 
-	// new button...
+	// new item...
 	if(options.new_item !== false){
 		var new_item = options.new_item || true
 		new_item = new_item === true ? '$New...' : new_item
@@ -1159,8 +1164,8 @@ function(list, options){
 					dialog.update()
 						.done(function(){
 							//dialog.select('"'+txt+'"')
-							dialog.select('"'+txt.replace(/\$/g, '')+'"')
-						})
+							txt 
+								&& dialog.select('"'+txt.replace(/\$/g, '')+'"') })
 				}
 			}))
 	}
@@ -1187,11 +1192,14 @@ function(list, options){
 				lst = dialog.__list[id]
 
 				// remove items...
-				to_remove.forEach(function(e){
-					var i = lst.indexOf(e)
-					i >= 0 
-						&& lst.splice(i, 1)
-				})
+				to_remove
+					.filter(options.remove 
+						|| function(){ return true })
+					.forEach(function(e){
+						var i = lst.indexOf(e)
+						i >= 0 
+							&& lst.splice(i, 1)
+					})
 
 				// sort...
 				if(options.sort){