Thanks John
Are you saying everything that works in TRS04 will also work with TRS09? That would really be a big incentive for me.
The big problem with TRS2004 was the fact that the error checking wasn't very good. Well written assets will work under both TRS2004 and TS2009.
In TS2009 compatibility mode the vast majority of TRS2004 assets will work, about 99%+ of them. TS2009 will flag errors but they will still work. Even running TRS2004 there are some assets that have errors in them that will not run correctly until you fix the errors.
TS2009 is more robust, I have some scripted wagons labeled TRS2004 that work perfectly if they are the only items installed but the TRS2004 scripting is such that the game crashes if certain other scripted items are installed into the same layout. As far as I am aware the same wagons run perfectly in TS2009 no matter what else is installed.
The TS2009 also gives you all the built in content from TRS2006, TRS207, TC1/2 and access to more of the DLS. It incorporates the steam locos enhancements etc. that are in TC3. Actually have a look at the TC3 web site
http://www.trainzclassics.co.uk under new features, these have all been incorporated in TS2009. Be aware that TRS2004 was written before Vista and is not quite as Vista friendly as TS2009. I seem to recall it requires some enhanced security permissions if you are running in a user level account rather than an admin level in XP but that could be TRS2006. There are sets of work arounds somewhere in the forum.
Additionally on the same hardware you get better frames per second in TS2009 than TRS2004. It also compresses the texture files which means the content creators can use bigger textures so things look better.
Basically you get more stuff that runs faster in TS2009.
Cheerio John