I succeeded in making a texture transparent.
Thank you,Phineus and ZOtm_BigDOGGe.

Sorry, I forgot to write I'm using mtm1.
Can mtm1 use "0x33 Transparent color #0 (mtm2)" ?
If you know how to make it, please let me know.

how does it turn out whether a part of texture is made transparently? Please let me know.

Thank you for a reply.
I understood a few.
Moreover, a question will be asked if it does not understand.

I want to make the Truck for MTM1.
Please tell me about how to make the Truck for MTM1.