Ok, I downloaded the files in the 3.0.3 release sticky thread here are the files in my mod folder right now:
my exec is fs2_open_3_6_9.exe (RC7)
Media vps are the latest with these patches:
not using adv_effects btw.
Launcher is pre-5.4
I select the mod folder fsport_3_0_3 in launcher and load the vps via this mod.ini:
SecondaryList = mediavps;
Also in the silent threat first mission, the ships appear with low quality textures, but maybe that's normal.
I hope this can help you solve my problem, thank you
edit: Seems to work now. Models and textures still have low quality though...