Those red squares happen if MM can't find the preview imageof a part.
(A MESHMIX part needs three files:
- the geometry (something.obj)
- the preview image (something.obj.png)
- the part's settings file (something.obj.prt)
These 3 files need to be in the same directory. In case of the shown Heads example and a default installation at:
...documents/meshmixer/libraries/parts/default/Heads )
Most likely there are non-latin chars (e.g. Cyrillic or Japanese ...) used in the path (maybe the name of your user account?). For some reason MM is able to find the part but not the preview image in those cases.
You can check if there's such path issue right clicking on a red square. You should get a tiny "CopyToClipboard" popup. Click it and paste to some text field (e.g. some text editor) to read clipboard's content. Something wrong with that path?
You may move the whole meshmixer directory to some different location on your system. Now if you start MM it will not find the meshmixer folder any more and a dialog will pop up. Use its Redirect button and browse to the new location point to the meshmixer directory.
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Your Google results link to the old MM forum. Unfortunately this does not exist any more.
