just managed to get RT3 running on windows 7 Home Premium, so here is a rough log of how to do it, ignoring the false starts, with some explanations.
If you understand how Windows generally works and read the W7 intro then you have a good chance of getting this to go - but be warned it is Windows, so if you trash your system I will not be able to give much if any help - so back it up before you start......
System has AVG anti virus + firewall in place.
The machine i use is an Intel quad core, running w7 home premium, 2 Gbyte of memory, Nvidia graphics card.
The system is set up with multiple user accounts and the default w7 security model - i think you might have to use an "admin" type account to operate the game since running in emulation mode gives access to hardware such as the DVD drive that w7 tries to protect - but i didnt check that box, so more testing......
Basic scheme follows the earlier instructions for Vista.
install RT3 as standard from the original DVD (v188.8.131.52 on my disk), then patch to v 1.03.
Alter the settings for video acceleration off in "Settings" - disable hardware T&L.
Patch coast to coast, v1.05, v1.06 (or stop at that point you like).
there are probably other ways to do this such as installing all the patches and putting the vista "engine.cfg" file in the Data\Configuration directory, but this was recommended for Vista and worked, so i let well alone.
While I was testing I managed to get the same symptoms with immediate crash at the main menu after patching to 1.06, and replacing engine.cfg fixed that......
Alter the icon you use to launch the program to run RT3 in XP SP3 emulation mode
(right click the icon, choose properties, go to the compatbility tab, and set the checkbox there, but leave all other settings default).
You will get a w7 security winge each time you start the program - i havent found how to fix that yet, but dont really care about 1 extra mouse click.
Tests so far are running the campaign for a single user, so this is no where near a complete set of tests - other stuff may need more tinkering.
The graphics at high quality is better than the w2k pentium 4 machine it replaces with the quality turned right up and doesnt affect speed, so software graphics is not affecting gameplay.
The only draw back so far is some wierd screen artifacts when starting / ending a game, or starting / finishing the program.
So - a few words of warning:
Vista and W7 both hide various files and extensions by default in file lists, which complicates this process - but changing the defaults could make "other stuff" look different.....
Any crash may lock files so that patches etc refuse to copy over the earlier version - a reboot should sort this out, or renaming the target file rather than copying over the top.
You can apply patches as often as you want as long as you do it the right order, so keep trying.
W7 has lots of security "model" things that can be tweaked, so dont be surprised if your system is set up differently and you have different results.
There are are at least 5 different types of W7 - this was "Home Premium".