Quote - I'm curious to know how big is your scene and how many textures you are using to make Poser "crash". Does it crash also with a max texture size of 512 pixels ?

If you mean me, the scene is two Millenium figures, both clothed and with hair, 3 scenery figures (all 3 sharing the same texture), and several plants (half a dozen, all sharing the same texture). All this on RDNA Macrocosm with a skydome; Macrocosm has a tiled texture, skydome a procedural one. So actually there are only 10 different textures @ 1024x1024: Two Mill figures skin and head (4) + 2 Hairs (2) + 1 dress (1) + Scenery figures (1) + Plants (1) + Macrocosm (1). The rest is Poser procedural textures.
No I didn't try to lower the max texture size to 512, since the final render is supposed to be 1200x1200 (trying and failing at 800x800 though).