Juud - have only just noticed this!
I have the same problem as you as I use the same program as you do.
The way I personally get around it is to organise my images as you have, and then copy an extra one at the beginning of the 'tiles' - doesn't matter which one as you'll be deleting it in a moment.
then i highlight the whole lot of them, place my cursor over the first image and then ask to 'rename'. I then rename them a name that is not already existing in the list of names that you have on there, and then press 'return'.
Hey presto, they are all called 'name (1)' followed by 'name (2)' and so on, except for your first one which is just 'name'. I then delete this one, and my images now remain in the order in which i wish them to be.
