diff --git a/BUGs b/BUGs
index 0b2fd3b..891f8ed 100644
--- a/BUGs
+++ b/BUGs
@@ -1,8 +1,3 @@
-moving a book:
-	with book 6 of 11, and there is no book 7: see series (Wars of Light and Shadow)
-		likely logic... if no bsl2, then just increase/decrease bsl1.book_num --> 
-		(it would also break if we had say books 1-5 & 8 and tried to move 8 down to 7)
-
 series does not deal with calcd_rating... 
 	(on edit could, recalc as a catch-all, and obviously if we change a single book's rating, we should re-calc)
 
diff --git a/main.py b/main.py
index 7d55204..10963c5 100644
--- a/main.py
+++ b/main.py
@@ -188,7 +188,10 @@ books_schema = BookSchema(many=True)
 ################################# helper functions ###################################
 def GetBookIdFromSeriesByBookNum( series_id, book_num ):
     tmp_book = Book_Series_Link.query.filter(Book_Series_Link.series_id==series_id,Book_Series_Link.book_num==book_num).all()
-    return tmp_book[0].book_id
+    if len(tmp_book):
+        return tmp_book[0].book_id
+    else:
+        return None
 
 def GetBookNumBySeriesAndBookId( series_id, book_id ):
     tmp_book = Book_Series_Link.query.filter(Book_Series_Link.series_id==series_id,Book_Series_Link.book_id==book_id).all()
@@ -222,11 +225,11 @@ def books_for_loan(id):
 def books_for_series(id):
     if request.method == 'POST':
         if 'move_button' in request.form:
-			# split form's pressed move_button to yield: dir ("up" or "down") and bid = book_id of book 
+            # split form's pressed move_button to yield: dir ("up" or "down") and bid = book_id of book 
             dir, bid = request.form['move_button'].split('-')
 
             book1 = Book.query.get(bid)
-			# if parent book, then up needs first sub book, if down then need last sub book (as parent book does not have a book_num in a series, its sub books do)
+            # if parent book, then up needs first sub book, if down then need last sub book (as parent book does not have a book_num in a series, its sub books do)
             if book1.IsParent():
                 if dir == "up":
                     tmp_bid = GetBookIdFromBookSubBookLinkByIdAndSubBookNum( book1.id, book1.FirstSubBookNum() )
@@ -235,37 +238,46 @@ def books_for_series(id):
                 moving_series_book_num = GetBookNumBySeriesAndBookId( id, tmp_bid )
             else:
                 moving_series_book_num = GetBookNumBySeriesAndBookId( id, book1.id )
-			# moving_series_book_num is the book_num of the book in the series we are really moving (adjusted for parent/sub book if needed) 
+            # moving_series_book_num is the book_num of the book in the series we are really moving (adjusted for parent/sub book if needed) 
 
             if dir == "up":
                 swapping_with_book_num = moving_series_book_num-1
             else:
                 swapping_with_book_num = moving_series_book_num+1
-			# swapping_with_book_num is the book_num of the book in the series we are going to swap with (notionally next/prev book in series)
+            # swapping_with_book_num is the book_num of the book in the series we are going to swap with (notionally next/prev book in series)
 
             tmp_bid = GetBookIdFromSeriesByBookNum( id, swapping_with_book_num )
-            book2 = Book.query.get( tmp_bid )
-			
-            # if book2 is a sub book, then we need its parent as book2 instead, as we have to move the whole book as one
-            if book2.IsChild():
-               book2 = Book.query.get( book2.parent_ref[0].book_id )
-
-			# By here: book1 is parent or normal book we are swapping with book2 which is parent or normal book
-            b1_numsb = book1.NumSubBooks()
-            b2_numsb = book2.NumSubBooks()
-            if dir == "up":
-                b1_move_by=-b2_numsb
-                b2_move_by=b1_numsb
+            # okay, if tmp_bid is None, then there is no book we are swapping
+            # with (rare case of moving say book 7 of a series of 10, and we
+            # don't have details on book 6 or 8...
+            if tmp_bid == None:
+                if dir == "up":
+                    book1.MoveBookInSeries( id, -1 )
+                else:
+                    book1.MoveBookInSeries( id, 1 )
             else:
-                b1_move_by=b2_numsb
-                b2_move_by=-b1_numsb
+                book2 = Book.query.get( tmp_bid )
+            
+                # if book2 is a sub book, then we need its parent as book2 instead, as we have to move the whole book as one
+                if book2.IsChild():
+                   book2 = Book.query.get( book2.parent_ref[0].book_id )
 
-			# By here: b{1,2}_move_by is the sign & amount we are moving the relevant book (and its sub-books by).  If it is a normal book,
-			# then its by +/-1, but if it is a parent book, then its +/- the num of sub_books as they all have to move too
+                # By here: book1 is parent or normal book we are swapping with book2 which is parent or normal book
+                b1_numsb = book1.NumSubBooks()
+                b2_numsb = book2.NumSubBooks()
+                if dir == "up":
+                    b1_move_by=-b2_numsb
+                    b2_move_by=b1_numsb
+                else:
+                    b1_move_by=b2_numsb
+                    b2_move_by=-b1_numsb
 
-            # MoveBookInSeries -> moves the book and its sub_books 
-            book1.MoveBookInSeries( id, b1_move_by ) 
-            book2.MoveBookInSeries( id, b2_move_by ) 
+                # By here: b{1,2}_move_by is the sign & amount we are moving the relevant book (and its sub-books by).  If it is a normal book,
+                # then its by +/-1, but if it is a parent book, then its +/- the num of sub_books as they all have to move too
+
+                # MoveBookInSeries -> moves the book and its sub_books 
+                book1.MoveBookInSeries( id, b1_move_by ) 
+                book2.MoveBookInSeries( id, b2_move_by ) 
 
     books = Book.query.join(Book_Series_Link).filter(Book_Series_Link.series_id==id).all()
     series = Series.query.get(id)
diff --git a/templates/books_for_series.html b/templates/books_for_series.html
index f56442d..1088c6f 100644
--- a/templates/books_for_series.html
+++ b/templates/books_for_series.html
@@ -45,18 +45,18 @@
 				{% if SeriesBookNum( series.id, book.id ) == 1 %}
 					<script>
 						{% if book.parent_ref|length %}
-							$('#up-{{book.parent_ref[0].book_id}}').addClass("disabled")
+							$('#up-{{book.parent_ref[0].book_id}}').prop("disabled", true)
 						{% else %}
-							$('#up-{{book.id}}').addClass("disabled")
+							$('#up-{{book.id}}').prop("disabled", true)
 						{% endif %}
 					</script>
 				{% endif %}
 				{% if SeriesBookNum( series.id, book.id ) == series.num_books %} 
 					<script>
 						{% if book.parent_ref|length %}
-							$('#down-{{book.parent_ref[0].book_id}}').addClass("disabled")
+							$('#down-{{book.parent_ref[0].book_id}}').prop("disabled", true)
 						{% else %}
-							$('#down-{{book.id}}').addClass("disabled")
+							$('#down-{{book.id}}').prop("disabled", true)
 						{% endif %}
 					</script>
 				{% endif %}