ID 443575 - Modo crashes when switching to mPath under specific conditions.

Problem summary

Modo crashes when switching to mPath under specific conditions. 

Customer reported version
14.1__14.1v1

Customer reported platform
windows10

Steps to reproduce

1) Open Modo and create a simple cube.
2) Add a HDR image to the scene for lighting.
3) Press the F8 key to open the Preview Render window.

4) With the item in view in the Preview Render window, go to the Shader Tree and select the Render item. Change "Default" to "mPath".

Expected behaviour
The renderer should be changed.

Actual behaviour

Modo crashes.

Workaround
Unknown.

Reproduced by support

This bug has been reproduced in:
Modo 14.1v1 - Windows 10 -regression

Unable to reproduce bug in:
Modo 14.0v2 - Windows 10

Earliest version tested

14.0v2 - This issue doesn't appear in this version and has regressed.