I want to do some major changes to existing characters like Victoria. To try it out I took her object file (blMilWom.obj), imported it into Wings3D and exported it again.
Just from doing this, the file size changed from 3.077 to 5,5442 MB. When loading my "new" Victoria into Poser 6, all I get is a blank screen - but no error messages.
So, how can I do that?
Or, is there a modeller which supports Poser properly? (Except Shade 7, which was the most horrible program I have ever used.)

i get that too.sometimes it takes a long time to load.if it takes more than 10 min i would not use it.

What kind of changes are you making to the geometry? 1. Changing the number of points (thru reduction or subdivision) will make the geometry useless for all existing morphs and may affect the UV mapping. Might even affect polygon groupings - don't know anything about Wings3D. 2. Moving the points is okay, but will change the correlation of UV mapping (introduce stretches to existing textures). 3. Some 3D modelling applications do not preserve vertex ordering which is crucial for morphs. 4. Wings3D might have introduced 'group segmentation' which is where you end up with many multiple sets of the same groups interspersed with one another. A large growth in .obj file size is indicative of this.

Wings does no. 4 to a lot of Poser figures if you use the original object file. Try loading Victoria in Poser, then exporting as an obj file. At this point, you can also turn off any elements you don't intend to change - hands and fingers, feet and toes for instance, and cut down the heavy polygon load. I found that Victoria is a little poly-heavy for Wings, but if you export just the bits you want to change, things work a little better. The problem lies with the Winged Edge data model used in Wings, which can't deal easily with some possible types of .obj - Wings needs entirely solid objects, while .obj can cope with single sided polygons or holes in meshes. THe conversion routine into Wings tries to deal with this by creating lots of little objects out of the original one. On the object browser in WIngs, you'll probably see lots of objects with the same name.

I have no problems moving .obj files back and forth from Blender. But before you look around for different modellers, realize that each is going to have its quirks, and import/export won't produce universal results. If you look hard enough, someone has always developed a work-around or a good plug-in to deal with a specific problem.