Hi,
You can change the stylesheets but NI does not support this. So you have to know how to do it on your own.
They are stored in: C:\Program Files\National Instruments\TestStand 4.0\Components\NI\Models\TestStandModels\StyleSheets. I highly recommend you copy them to: C:\Program Files\National Instruments\TestStand 4.0\Components\User\Models\TestStandModels\StyleSheets. Notice the difference is NI vs User. That way you still have the original stylesheets. There's a wonderful xml tutorial here:
http://www.w3schools.com/xml/default.asp They do have Javascripts in them so you will have to figure that out as well. If I were you I would copy an existing stylesheet (out of the 3 provided) and then add to it and change the name. That way you can easily revert back to the old ones. You can choose your stylesheet when you change the report options.
I don't understand how you can open a file in Excel without first generating it. If you just generate a temp file you still have to generate something. If you want the report to open up directly in Excel you first must make sure that excel supports your stylesheet and scripts. Then you can change your External Viewer to be Excel.
Configure>> External Viewers...
Add and browse to excel.exe (C:\Program Files\Microsoft Office\Office12\EXCEL.EXE) or something like that depending on your version of Excel.
Change the format box to xml
check the Automatically Launch Viewer box.
If you are sick of the xml files being populated on your machine you can check the User Temporary File box in the Report Options.
Hope this helps some. Let me know if you have any quesitons,
