Scripting problems with upgraded project file

I hope someone can offer a bit of help on this one. I have a v3 project file that I upgrade to v4. I decided to add a "return to menu" script to this project file. 3 scripts to set GPRM 0 mov to 0,1,2 for three different menus. And a final Jump script to Jump to Menu 1 if GPRM 0=0, Jump to Menu 2 if GPRM 0=1, Jump to Menu 3 if GPRM 0=2.
This doesn't work - won't work in simulator nor on a build. I suspect that the culprit is the upgraded project file. I made a new v4 project file and replicated these same exact scripts and behold! It works!
So I figured out that it's the upgrade project file that is the reason why these scripts won't work! Very disappointing.
But now, what can I do short of rebuilding this project all the way from scratch?!?
It's too bad you can't open 2 projects and copy and paste from one into another.
Using DVDSP 4.0.3
Dual 2 ghz G5   Mac OS X (10.4.5)  


If you'd like to strip out the project assets (video and audio) and use .pict images as place holders instead, then send me the file (with the place holders), I'll happily take a look at it for you. It should be working fine, and I suspect there is something small we have both overlooked.
There are no real issues with projects from v3 going on to v4 where scripting is concerned - the scripts are identical. There will be something else going on here...
Just to be sure your scripts are:
mov GPRM1, 0
Jump MainMenu // your actual menu name is here
mov GPRM1, 1
Jump SceneSelection1 // again, your actual menu name is in here
mov GPRM1, 2
Jump SceneSelection2 // and again for the menu name
Then your final script reads:
Jump MainMenu If(GPRM1 = 0)
Jump SceneSelection1 If (GPRM1 = 1)
Jump SceneSelection2 If(GPRM1 = 2)
The first script is the start up item for the disc, the second and third scripts are set as targets for buttons on the main menu (which means the script is run before the footage plays) - the last script is set as the menu call and end jump for the track.
You are sure that you are correctly re-setting the GPRM each time you move between menus?
If this simple scripting system isn't working then there is going to be a reason for it besides the upgrade... send me the file, I'll have a look. Alternatively, have a look here for downloadable stuff, and find the zip archive called 'Chi-Ho Lee', which is a simplified PAL version of how I think you should have this set up.