In the styling.java is a line 87
List<IMendixObject> stylesObjects = Core.retrieveXPathQuery(context,"//" + MxCellStyle.getType()
+ "[XLSReport.MxCellStyle_Template='" + TemplateObject.getMendixObject().getId().toLong() + "']");
an improvement is:
List<IMendixObject> stylesObjects = Core.retrieveXPathQuery(context,"//" + MxCellStyle.getType()
+ "[" + MxCellStyle.MemberNames.MxCellStyle_Template +"='" + TemplateObject.getMendixObject().getId().toLong() + "']");
Maybe this will gives you a java error so you can see something is renamed.
My guess is that the module was renamed from XLSReport to XLSreport (with a lower case R )
The module uses fixed naming at the line Chris pointed out, thus it fails there.