*.B3D doesn't work with masked textures!

Add this to the top of your code

Const FLAG_COLOR  = 1
Const FLAG_ALPHA  = 2
Const FLAG_MASKED = 4
Const FLAG_MIPMAP = 8
;etc... For the rest of the different texture flags

Then change this line:

WriteInt(file,masked)                ;flags (alpha..)

To this:

WriteInt(file,FLAG_COLOR Or FLAG_MASKED)

And add whatever other flags you want by using 'Or'...

That should do the trick,
Fredborg