Sagana was right : I start a project in body shop (cloning the blue underwear that has the same shape has the pink nice one) and the project package looks exactly like my file : flag 0 no creator string and no binary index....
So instead of fiddling with simpe (as I don't know what I'm doing, I finished my project in bodyshop, importing the texture from the pink undies.
I hope now they will be buyable but even if it works, I know that my sims currently wearing it would have reverted to some maxis undies as it no longer is the same file (I clone it in bodyshop)
Big thanks once again to maxon, bitsy and sagana.
I'm off to hunting the swimsuit and teen male pajama to do the same, but will leave the elder and teen female undies alone : they are not worth the work in my opinion.
If anyone know of quicker way to find the package than to open every file, I'm interested.
pioupiou
Excellent - that makes perfect sense.
I'd look at the textures with Clean Installer - they pop up in the little box when you click on the file - it will also tell you all the information you need, including the filename. Even easier, you can use the programme to move the file to an empty folder.