with current Houdini versions (starting with 15.5.553, I believe), I get the following error message when starting a render:
mantra: /shop/principledshader1/SurfaceVexCode:7171:20-30: Error 1066: Call to undefined function ‘getuvobject’.
/shop/principledshader1/SurfaceVexCode:7172:25-40: Error 1066: Call to undefined function ‘getuvhiresobject’.
mantra: Failed to resolve VEX code opdef

It doesn't matter whether I use the mantra surface shader or a simple principledshader.
I'm using Windows 10 pro on a HP Zbook 15.
Any ideas anybody?
Regards,
Carsten