Issues with displaying of the model in the game

[bonesz]

Guys, I have an issue with the model displaying in the game. In the Cubik Studio it displays ok. Like the block on the floor it looks ok, but unlike it in the hand (1st person view) it looks really awful, like it's transperent. From the beginning I thought it was because through voxelization I used the option "Keep empty inside", but the same without it. Please give me some advice how should I solve this problem because my customer waits for the model and my deadline is very close.

[Sphax]

I think the problem is due to the block you are using for your 3D model.
Try using a block which does not support alpha-transparency (ie. most blocks such as stone, stairs, ...). Do not use glass, glass panes or ice for example.

[bonesz]

I think the problem is due to the block you are using for your 3D model.
Try using a block which does not support alpha-transparency (ie. most blocks such as stone, stairs, ...). Do not use glass, glass panes or ice for example.

Yeah, I think it caused by transparency. But can you tell me, how I have to use another block? I'm new actually. Thank you beforehand