soo i created using only SimPE and blender this new bodyshape based on bobbyth bootylicious v2dd, but i am having lots of issues:
and when i click f6 this happens:

why the body is still in t pose mode??? and why is the nesk unlinked with the body?? what should i do??

Have you made sure the body has joint assignments? Otherwise the body won't be animated at all.
It's probably also what's wrong with the neck. It needs to have the same assignments as the neck of the head/face. If it doesn't, you get a gap.

Can you maybe upload the files (mesh + recolor package files, possibly also Blender file)?

no, i selected the correct joint definition in the order "xyz"
anywayss help me plz i am DESPERATE

Considering the mesh is an OBJ, that explains pretty much everything. OBJs can't carry a skeleton or joint/bone assignments, so if you make anything meant to be animated, they are pretty much useless (but work fine for non-animated meshes). SimPE allows you to replace the mesh with an OBJ, but won't give it joint assignments, which means it won't move at all with the skeleton.

Joint assignments are what links a mesh to a skeleton. Essentially you link each vertex to a joint, so when you move that joint in the skeleton, the vertices linked to it moves together with it. Vertices can be linked to one or more joints, depending on placement.

Working with Blender, you'll probably want to have a look at this plugin: http://modthesims.info/d/612164/upd...ender-2-79.html
There are some tips in the comments, but basically you can use any tutorial originally for Milkshape and replace the Milkshape bits for Blender. Not sure if the maker of the plugins made a tutorial, though.

If the mesh you want to use doesn't have joint assignments at all when you start working on it, or is from another game, you may want to look into 3t2/4t2 conversions, as they show how you can transfer usable joint assignments to an OBJ mesh. This will often require some fixing, as the method isn't perfect.

If you have a version of the mesh with proper joint assignments, you'll instead want to use that one.

the mesh i used to start working does have joint and bone assignment, i only wanted to edit the bootylicious v2dd mesh created by bobbyth, which was very active on backalley sims. do you think that converting the body from obj to smd will make the body work??? i can also make smd meshes with my blender version

EDIT: it doesn't install, i have version 2.80

Pretty sure you need plugins to make this work. Not entirely sure about SMD - the last tutorial for Blender using SMD was written in 2007 with a much older Blender version, and it looks like the meshes had some rather unwanted flaws in regards to normals. I don't think you can use the 2.80 version with the plugins.

You can however use several versions of Blender at the same time (get the noinstall version if available, and put the files in another location - they can coexist, but they may behave a bit strange if you auto install a second one).

Old Blender tutorial with link to script used (not making any guarantees this will work, since it's made for an older Blender version) - http://modthesims.info/t/248699

You don't have access to Milkshape, by any chance? It would work better with TS2 meshes, and you'd probably not have to do any bone assignments. Milkshape is still one of the most used tools for making clothes in TS2.

YEAH, i have finally installed milkshape3d 1.8.5 and here the skeleton is visible, but what should i do?? Should i select vertices and assign them to the bone structure?? Because i tried but the mesh at the end was always unlinked

If you're working with a mesh that originally was a TS2 mesh, then the easiest would be to start over, because then you get the exact bone assignments - extract the GMDC you started with (Right-click the GMDC in SimPE, choose "export" which gives you two "5gd" files (5gd + XML) - don't use the "export" button down in the Plugin View because that one gives you an OBJ), and do the edits over again. Then import these files to Milkshape with "file --> Import --> Sims 2 Unimesh Import". When you're done, use the "Sims 2 Unimesh Export" to make it into a file SimPE can import, then right-click + import, choose file - Don't use the "import" button!)

I don't recommend manually adding bone assignments (had a look, and the mesh is quite high-poly, so that's a lot of work - it's tedious enough with lower-poly meshes), or if you absolutely want to use the OBJ mesh you may have to look at the method of how to transfer the bone weights in 4t2/3t2 conversion tutorials with a few tools (but skipping most of the other parts)
3t2: https://serenity-fall.dreamwidth.org/1366.html
4t2: https://www.youtube.com/watch?v=-_4J2lBu6Cs

(By the way, "bone" and "joint" assignments are the same thing, so you don't get confused )

Ok i will try!! Anyways thank for ur help but i find it quite hard to edit meshes in milkshape, so if i etract the mesh in 5gd i can only use milkshape?

You can use Blender to do edits, but you need to use the correct version and the belonging plugins.

Unfortunately there are very few tutorials using Blender for TS2 edits, and there don't seem to be a lot of people who are using it, so getting help with it could be a bit difficult. I have some experience but have only barely tried out the plugins (I use it for meshing and such, but rarely for making clothes). There was a tutorial at an older site called SimOasis, but the site went down a few years back, and since then I've only seen one or two tutorials for Blender and TS2.

Milkshape is a bit more difficult to edit in (I don't think I've ever made a mesh from scratch there, either) but for simple edits and bone assignments it's fine. It has a few advantages, like playing a bit nicer with normals, but it suffers from not having a usable 3D view.

so now i should use the etracted file and modify it in milkshapr

It's up to you.
Blender can work, but you need to use a lower version and read up on how the plugins work (few tutorials to work with, so you need to figure out what to do)
For Milkshape there's several tutorials and all that, but the 3D window is only for viewing, so reshaping can be difficult.
You can start over to get the proper bone assignments, or you can try to assign new ones via the 3t2/4t2 method (from the steps where you have a ready OBJ file without bone assignments).