FreeGameDev

i found a small bug, this is not the first time it happens

you can see, that in blender the normals go outside, but when i start the game, the normals go inside

try applying scale to the model and then recheck the normals. that should fix it.

i will try it
some days ago i made my bottles here (viewtopic.php?f=17&t=4540), first they were "flying" in the air and applying scale and after applying scale this worked

it workes

probably the object had a negative scale, this causes all kinds of problems including what you noticed

yes, after applying scale the faces normals are on inner-side, so i had to recalculate/flip the normals