P3D v4 AA makes my semi-transparent texture disappear ?

Hey !

Since my dev PC doesn't have a descent GPU, I use P3D with AA off. When testing my scenery on my main PC I found out that my ground polygon was turning almost transparent with AA on MSAA x8.

Have a look :

MSAA x8 :

AA disabled :

The texture is in DDS dxt3, I can provide it if needed.
What happen? Should I try to make my texture less transparent or Is there a setting in MCX to prevent this?

Thank you for your help, have a great week end !
Alright I made it less transparent, just enough to be able to see the ground details through it and its seeable even with MSAA x8.
Easy to solve but weird reaction from P3D.