Copyright (C) 2009-2021 The OpenSCAD Developers
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
I found the solution. I just had to download all files and open it from the extracted folder....
Close my issue, please.
I freshly installed OpenSCAD version 2021.01.
When opening your models there are different problems like this:
OpenSCAD 2021.01 https://www.openscad.org/
Copyright (C) 2009-2021 The OpenSCAD Developers This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
Loaded design 'C:/Users/---/Downloads/gridfinity_basic_cup.scad'. WARNING: Can't open library 'gridfinity_cup_modules.scad'. Compiling design (CSG Tree generation)... WARNING: Ignoring unknown module 'basic_cup' in file gridfinity_basic_cup.scad, line 71 Compiling design (CSG Products generation)... Geometries in cache: 0 Geometry cache size in bytes: 0 CGAL Polyhedrons in cache: 0 CGAL cache size in bytes: 0 Compiling design (CSG Products normalization)... Normalized tree has 1 elements! Compile and preview finished. Total rendering time: 0:00:00.050 Loaded design 'C:/Users/---/Downloads/gridfinity_baseplate.scad'. WARNING: Can't open include file 'gridfinity_modules.scad'. Compiling design (CSG Tree generation)... WARNING: Ignoring unknown variable 'gridfinity_pitch' in file gridfinity_baseplate.scad, line 72 WARNING: undefined operation (undefined / number) in file gridfinity_baseplate.scad, line 72 WARNING: undefined operation (undefined - number) in file gridfinity_baseplate.scad, line 72 WARNING: undefined operation (undefined - number) in file gridfinity_baseplate.scad, line 72 WARNING: Ignoring unknown module 'cornercopy' in file gridfinity_baseplate.scad, line 74 WARNING: Ignoring unknown module 'gridcopy' in file gridfinity_baseplate.scad, line 77