I converted the Red Bull Arena (home of Bundesliga team RB Leipzig) from EA Sports WC 2006 game to FIFA 07-09 and edited some textures and models. Now you can use it with animated crowds, lights, adboards etc. in game. Download here.
I replace files normally with creation master but also tried file master, bigGUI and finalBIG. Always works with original files and any other .o file , so i guess thats not the problem in any way. Only when i try to import one of edited files with o-tools it makes problems.
For import or export?
No .o file created with o-tools works in game. With or without textures (normally it does work even without textures).
First of all i had to install d3dx9.dll manually that o-tools even work.
And why you cant open any .o file created with o-tools in other tools i normally use to work with...