However %x strings work fine for me, Win7 64-bit, SketchUp 2016 Pro 64-bit.
The Kernel
backquote method was bugged early in SketchUp with Ruby 2.0, I think either v2014 or v2015 initial release. But I thought it was fixed in a later maintenance release. (%x strings use the Kernel
backquote method.)
See my post: [code] Backquote method patch as Mixin module