21 Jan 2019
— Edited @
03 Nov 2021
I just found how to fix it.
The installation guide in the document for developers included in ANSYS-VABS GUI just works well with Mechanical APDL 15.0.
It says that the file name 'menulist###.ans' should be modified according to the installed ANSYS version.
Instead, newer versions only support 'menulist.ans' without any mixed numbers.
The contents of the menulist.ans follow the installation guide.
Hope that anyone who suffers can be relieved.