VS2008 & .NET FW 3.5 SP1 Beta - possible problems and solutions/workarounds (mainly focused on Entity Framework, but not only)

Couple of links I've found during recent days:

Visual Studio 2008 Service Pack 1 Beta Readme
Visual Studio 2008 and .NET Framework 3.5 Service Pack 1 Beta
VS 2008 SP1 beta installation problems and suggested solutions
Re: VS2008 SP1 Beta fails to add "new item - ADO.NET Entity Data Model" Item Template
Can't find the Entity Data Source?
Entity Framework Breaking Changes - Visual Studio 2008 & .NET 3.5 SP1 Beta

(in particular to have it on some place and not to lose it :))