Bug Report: Error after pressing “BEGIN NEW GAME”

[ryomaco_514]

https://imgur.com/a/BQWrUxL

Does anyone know how to fix this error?

---------------------------
Microsoft Visual C++ Runtime Library
---------------------------
Assertion failed!

Program: ...common\Classic Marathon\Classic Marathon Steam.exe
File: D:\a\alephone\alephone\Source_Files\Render...\shapes.cpp
Line: 1640

Expression: bitmap

For information on how your program can cause an assertion
failure, see the Visual C++ documentation on asserts

(Press Retry to debug the application - JIT must be enabled)

[Dosto]

The game looks totally distortioned on green lines, i can't even see the menu correctly.

[ryomaco_514]

The cause was found.
Disabling the plugin “Hi-res weapons(M1A1) 0.1” solved this problem. But why?
I would like to see an improvement.