It all depends what language and target you are using.
1) EFContext is handled only by C# for CSLA40. Most (if not all) new features are available only for CSLA40.
2) IsDirty/IsValid aren't used in CSLA40. I had a bird look at the templates and found no comments near neither. Old templates are suppose to keep generating the same code as before. What language and target are you using?
3) C# for CSLA40 has no rules available but old templates are suppose to keep generating the same code as before. What language and target are you using?
Keep in mind CslaGenFork is all about CSLA40 and for the moment there are only C# templates. There will be no evolution for older templates unless someone takes that task in charge. The legacy issues is answered on the FAQ you can find at http://cslagenfork.codeplex.com/wikipage?title=FAQ&referringTitle=Home -
How will CslaGenFork handle the legacy issue?
If your target is CSLA35, you can try CSLA40 target provided you don't use authorization. Oy maybe you can use it and edit the generated code.