@greengeek :-
This is a pretty straight-forward one, Ian. Take a look at the /root/Choices/ROX-filer/PuppyPin file. This file controls the exact, to-the-pixel, positioning of every single icon on your desktop. It also determines the background wallpaper in use.
This is a dynamic, or 'live' file. Any changes made on the desktop are immediately written to the PuppyPin file.
I had a spell - some years ago - of the 'pinboard' periodically going AWOL. If I'd been using the default layout all the time, it would have corrected itself at next boot. However, I use a highly-customized and -personalised layout, and it was really annoying to have to keep setting it all up every time.
Ever since then, I've had scripts in place that save the current state of the PuppyPin file to an external location at every shutdown.....and further scripts that allow me, via a Menu entry, to 'reset' the desktop (if it ever happens again) by overwriting /root/Choices/ROX-filer/PuppyPin with my own version, then re-starting "X". Works a treat.
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Your issue probably occurs due to the 'triangle', as you call it, taking its 'x' & 'y' co-ordinates from the top and left-hand edges of the screen.....but the drive icons are positioned from the left-hand & bottom edges of the screen.
ROX 'standardises' icon size to 48x48 if they're larger to begin with. It IS possible to make them smaller to start with, then ROX will use them at this reduced size.
You can restore normal appearance by careful re-positioning of all items on the 'pinboard'; perhaps moving the lines of icons slightly closer together, moving the top line a bit closer to the top edge, the whole triangle a bit closer to the left-hand edge, re-positioning the drive icons closer to the bottom edge. Either do it all manually, then save a copy of the PuppyPin file immediately before shutting down.....then re-master your main SFS to include this instead. OR; carefully work out all your geometry and re-write the PuppyPin file before re-mastering.
Either approach should work.
Mike.