Welcome to the desert. There is very little Metre Gauge about (someone please prove me wrong). One layout is Carhaix but it needs a bit of working on and some of the assets are not on DLS. There are several mallets on DLS as well as some coaches. You could use 42" Gauge stuff but again not too much around. Patricia has some Metre Gauge on her site but I have found trying to get into it is like opening a sardine tin without a key or swiss army knife. Sir Gibby has 42" Chilean Nitrates (freeware) as does Barn700 (payware). I believe there is some metre stuff in Eastern European sites but my lack of foreign languages from that area puts me at a disadvantage.
A lot of swiss meter gauge, including a map, are available at shanemoritz.ch. Download is free.
Searching the DLS for rhb will get you some more swiss meter gauge material, including the RhB Crocodile by Witte46 (each locomotive has 3 parts: A, B and C).
Patricia Trainz2004 has more centent from Switzerland, including maps and rolling stock in meter gauge. You have to register to download.
A couple of times I've toyed with doing something metre gauge and indeed, there's surprisingly little (compared to 600mm/2ft or 760mm gauges). Would be nice if the assets on the sites referenced above could be included on the DLS, though understandable if the authors don't wish to do so.
Unfortunately there isn't all that much 1 metre gauge stuff for Trainz on the DLS & third party sites. Over the years I've looked high & low for the stuff. There is some, but in my experience there seems to be a lot more 3ft (36 inche) stuff available. Especially steam loco's & rolling stock...
It's usually found under 3ft - 36in - 36ng - etc!!!
I have been trying for about six months now and with different passwords supplied by Patricia but still no entry. If you come up with a solution perhaps you drop a post.