Hi,
Sorry if this is unrelated, but as seeing this is a post about the beta, here goes.
I've installed the Beta 4 and have recently updated to 4 Beta 20 from an earlier version. It opened up fine the first few times, but now it gives me the following message:

Application Error
Unable to launch the application.
Name: Sweet Home 3D 4.0 Beta
Publisher: eTeks
From: http://www.sweethome3d.com

Then, there's two buttons: Ok and Details.

If I click details:

Error: Failed to validate signing of launch file. The signed version does not match the downloaded version.

Then there's a tab "Launch File" with a bunch of code and a tab "Exception" with a bunch of info.

I don't know how to fix this. I've tried reinstalling, rebooting, ending the process manually, etc.

If you need either of the texts under those tabs, let me know.