Hi infos,
Thank you for your post.
If i understand, you have Two content types TdC1 and TdC2. You would like to have in the first one only category cat01 and for the seconde one only category cat02.
In other words, you want to force the user to save articles of TdC1 in category cat01 and articles of TdC2 in category cat02.
To do that, i advise to select variation hidden for the field "Article Category Id" in both content types. Then you click on button "2" to set a static live value (you can click on the arrow which appears to help you to select the right value).
Regards,
Mehdi.