I did import a file with 90 columns using the provided demo example and it is working as expected.
Could you please confirm that importing the file using the demo is causing a misalignment again or not. This will help us determine if there is anything specific with the data in the file, or with the custom implementation of the Spreadsheet.
I will be expecting the additional information to continue with the investigation.
Telerik by Progress
Kendo UI is ready for Visual Studio 2017 RC! Learn more.