I started using LabVIEW when it was at version 6 and have used all the interim versions. I have always found the implementation of the Alt-Tab keystroke to be irritatingly inconsistent with other Windows applications.
If we have multiple LabVIEW wnidows open, for example, Alt-Tabbing to one of them means I have Alt-Tab through ALL of them to get to the first non-LabVIEW window. This is a real menace. If we have, for example, 8 LabVIEW windows open and the Calculator, we just want to Alt-Tab between LabVIEW and Calculator: we have to tab 8 times to get to the calculator but once will get us back to LabVIEW.
This makes little sense, since Ctrl-Tab has historically been for tabbing between multiple instances of the same application. Alt-Tab should be reserved for tabbing between applications.
By contrast, if we have multiple Microsoft Word documents open, they are mixed in with the other applications on the Alt-Tab popup, so if there's one which hasn't been topmost for a long time, it gets shoved to its rightful place at the end of the list.