We are using Infragistics 10.1 Version controls in one of our project.We have the below mentioned problems in the application. In the UltraWebGrid, if we set the AllowColSizingDefault=Free, Columns resizing is not working properly and also sorting and filtering is not working in the grids, Controls are not rendering properly in all browsers except IE7 and IE 8.If we upgrade our project from 10.1 version to higher versions (11.1,11,2 and 12.1) , which version will be resolved the above mentioned problems?If we upgrade the project to higher version then what are the changes required in our project means if we upgrade the higher versions controls on the existing version ,is it required to change all the properties and methods of existing controls through our application ? or its required liberal (minimum) changes in the application?And also we have required extra features like Multicolumn sorting and multi grouping on data in Web Grids ,Calendar Controls .If possible could you provide the features of the higher versions with differences.We have the urgent requirement, please provide response as soon as possible.