Hi guys, I'm new to this site, so I apologize if this topic has been discussed before. Unfortunately, I couldn't find answers to my questions on this site, because I'm still new to converting CC content from Sims 4 to Sims 3. I tried to search by keywords, but I couldn't find anything. Although I don't rule out that I just didn't write the terms correctly (I don't speak English well, sorry), so I could have written something wrong when searching.

In general, let's get to the bottom of my problem. I'm doing a conversion based on this YouTube video "TSR4 to TSR3 clothing conversion tutorial | for beginners!" (Nighto).

I did everything according to the manual, but I still had problems. I have a problem with the scales. When I change the sliders of weight and muscles, my character is just terribly unnaturally deformed. As the artificial intelligence explained to me, this is the problem with the scales, that they either did not transfer correctly or did not transfer at all. I don't know why, I did everything according to the manual. Then I tried to find where I could download the body completely with the correct weights in order to transfer all the weights from it to the blender, just to be sure, because in my current clothing model there are now completely empty weights, I deleted them all, since they belonged to the Sims 4, I thought that they were not needed for the Sims 3, and deleted them. I have not been able to find where to download such a body reference. I would appreciate it if you could tell me where to download them. I don't know why transferring weights and morphs to meshtoolkit didn't work for me the same way as in the video. The version of meshtoolkit I have is 1_4_9_2. I would also like to add that I skipped the step of working in milkshape from video because I found a guide on this site on how to do it in a blender. I preferred the blender option because it was more convenient for me. I think this is all about the mesh itself. But I also have another problem with the texture. For some reason, mine (mask) is not working properly, although I am sure that I did it completely correctly, as well as I did it correctly (multiplier). I should have three areas for different repainting. But nothing is working. Everything is repainted with only one color. The only difference between me and the video I used to do it. It was because the author of the video texture (multiplier) had a light gray texture when he uploaded it to his mesh. And my texture, when loaded onto the mesh, was very black, not gray. Although I didn't save it in the normal light gray color. But when uploading to tsr workshop, it turned black.
That's all, I hope someone can help me with my problems. Thank you all very much in advance for your help.

Often, the easiest thing to do is upload what you have, and someone can take a look, and probably find where things went sideways.