1. The file is not in UTF-8 encoded – not sure if this is the problem, but when I opened in the exported json string there was a syntax error in onselectCell function. Please check this.
Try not to use them in the export string and see if this is the problem.
Navigator options including filters are not part of the grid. You will neeed to create your own jsonstring. See the code for exportGrid (it uses a very simple code) or use importComplete to build the navigator when