I have been using PEVs AttachmentMaker for some time now to attach scripted tail lights, swap bogeys in order to change gauge, swap couplings and to add visible loads. This piece of software, used in conjunction with his other offerings, has really enhanced my enjoyment of trainz.
There were instances, however, where the adaptations weren't really satisfactory. This was mainly because the rolling stock body was too high off of the track for my favourite 3ft 6in gauge, often resulting in the couplings and or bogeys 'floating' below the body of the item - also one or two items of rolling stock were significantly out of loading gauge, the body being too high overall.
SO, I experimented with AttachmentMaker some more to see if there was a way to lower the rolling stock body (mostly by no more than 200 or 250mm or so) in order to better integrate bogeys and couplings with the rolling stock body and/or to comply (more or less) with loading gauge.
As a result I have succeeded in doing this so as to meet the requirements of 3ft 6in loading gauge and to add to and expand available consist options.
Also, I have kitbashed a full range of generic colour light signals for my own purposes - next trick is to script some of them, 'though I'm not hopeful.
I am not claiming, by the way, that the resulting stuff is in any way prototypical - I work on the old freelance modelling principle that if it looks right, it is right - my own routes and layouts are imaginary, set in a warm-temperate climate somewhere in the Southern Hemisphere, nowhere in particular but looking a lot like where I live.
Finally, a word in favour of Asset-X (not the most intuitive piece of software) which as aided me in upgrading everything to TS2010 standards so that I can run exlusively in native mode.
The original asset creators need to be acknowledged - I couldn't have such fun without them.
Note: this message is repeated in Screenshots Forum with images of examples added. Title 'PEVs AttachmentMaker at work' ('though the images are too small and will be replaced).