Index: src/depot_gui.cpp
===================================================================
--- src/depot_gui.cpp	(revision 27935)
+++ src/depot_gui.cpp	(working copy)
@@ -383,12 +383,13 @@
 			int col = _colour_gradient[wid->colour][4];
 			int image_left  = rtl ? r.left  + this->count_width  : r.left  + this->header_width;
 			int image_right = rtl ? r.right - this->header_width : r.right - this->count_width;
+			int first_line = w + (-this->hscroll->GetPosition()) % w;
 			if (rtl) {
-				for (int x = image_right - w; x > image_left; x -= w) {
+				for (int x = image_right - first_line; x >= image_left; x -= w) {
 					GfxDrawLine(x, r.top, x, r.bottom, col, 1, 3);
 				}
 			} else {
-				for (int x = image_left + w; x < image_right; x += w) {
+				for (int x = image_left + first_line; x <= image_right; x += w) {
 					GfxDrawLine(x, r.top, x, r.bottom, col, 1, 3);
 				}
 			}
@@ -734,7 +735,8 @@
 			}
 			/* Always have 1 empty row, so people can change the setting of the train */
 			this->vscroll->SetCount(this->vehicle_list.Length() + this->wagon_list.Length() + 1);
-			this->hscroll->SetCount(max_width);
+			/* Always make it longer than the longest train, so you can attach vehicles at the end, and also see the next vertical tile separator line */
+			this->hscroll->SetCount(max_width + ScaleGUITrad(VEHICLEINFO_FULL_VEHICLE_WIDTH + 1));
 		} else {
 			this->vscroll->SetCount(CeilDiv(this->vehicle_list.Length(), this->num_columns));
 		}
Index: src/train_gui.cpp
===================================================================
--- src/train_gui.cpp	(revision 27935)
+++ src/train_gui.cpp	(working copy)
@@ -64,14 +64,14 @@
 	bool rtl = _current_text_dir == TD_RTL;
 
 	assert(selection != INVALID_VEHICLE);
-	int dragged_width = WD_FRAMERECT_LEFT + WD_FRAMERECT_RIGHT;
+	int dragged_width = 0;
 	for (Train *t = Train::Get(selection); t != NULL; t = chain ? t->Next() : (t->HasArticulatedPart() ? t->GetNextArticulatedPart() : NULL)) {
 		dragged_width += t->GetDisplayImageWidth(NULL);
 	}
 
-	int drag_hlight_left = rtl ? max(px -dragged_width, 0) : px;
-	int drag_hlight_right = rtl ? px : min(px + dragged_width, max_width);
-	int drag_hlight_width = max(drag_hlight_right - drag_hlight_left, 0);
+	int drag_hlight_left = rtl ? max(px - dragged_width + 1, 0) : px;
+	int drag_hlight_right = rtl ? px : min(px + dragged_width, max_width) - 1;
+	int drag_hlight_width = max(drag_hlight_right - drag_hlight_left + 1, 0);
 
 	if (drag_hlight_width > 0) {
 		GfxFillRect(drag_hlight_left + WD_FRAMERECT_LEFT, WD_FRAMERECT_TOP + 1,