I have 4.1 installed and working.
I have Microsoft .NET Micro Framework 4.2 QFE2 SDK
and 4.1 QFE1 SDK
In installing GHI Software Package v4.2 I get:
A network error occurred while attempting to read from
the file: c:…\GadgeteerCore(1).msi
The file exists but not as the (1) version
I downloaded a 2nd time, unpacked and tried again - same result
What am I doing wrong?
Tom Dean
[quote]I have Microsoft .NET Micro Framework 4.2 QFE2 SDK
and 4.1 QFE1 SDK[/quote]
You must remove everything 4.1 and older from your PC before installing 4.2 please.
I am making a presentation about Gadgeteer, using GHI products, at the 12/15/2012 meeting of the Seattle Robotics Society, and making all my modules available for a hands-on demonstration at the following afternoon workshop.
At this late date, I think it better to remain at 4.1.
Are ther any gotcha’s in upgrading? What are the advantages of upgrading? I most likely will be asked these questions.
Tom Dean
The requirement in when you upgrade your SDK is about making sure you then update all your mainboards’ firmwares to that new level. That can take a while when you have a menagerie of boards like I seem to. 
Don’t forget to uninstall the Seeed programs (i think there were 2 of them, but could have just been me.). I didn’t notice them when I updated to 4.2 and my Seeed modules weren’t working in Visual Studio, but once I uninstalled them and updated to 4.2 it was all good.