Edhy,
I was using PostBuild 2007Pro also. A while ago (many months) we stopped using it. In our case, there wasn't a compelling need to use it, verses the hassle of getting it right. However, here are some things I found.
First, be careful what you obfuscate! The important thing here is to know what SF serializes as text. It is pretty unsafe to obfuscate any BO or any enum as these are used to fill listbox/comboboxes and they serialize the names as text. Thus if you obfuscate the name or fill methods of the BO, it breaks.
I also was doing this with ClickOnce, so it was more complicated. I'm hoping you don't have that pain.
I believe the process I used was:
1. build a release version
2. Select the files to obfuscate
3. I used aggressive I think
4. I would then deselect BOs and Enums that were likely to end up serialized.
5. I seem to remember something about needing to allow IDLASM tools, but that was probably for ClickOnce.
6. Set flow control settings to 4 I think
7. I typically would encrypt strings also. I was encrypting any sql strings embedded within the app. If I was really concerned, I'd just use sprocs for all access to db though and have no sql embedded. This was a pain as you'd basically have to set this up every single time you do the build (i.e. your saved setting would likely need to be updated).
8. I don't remember much of the other options, except I did multiple assemblies (for ClickOnce).
I'd also recommend looking into using attributes to control the obfuscation process. I think you mark types that aren't obfuscated. This allows better control and simplifies the obfuscation process.
I would recommend that when you are coding to NEVER use a string to indicate a type. I.e. you'd never use something like MyBOType = "MyProject.BusinessObject.MyBO". Instead, you'd use MyBOType = GetType(MyProject.BusinessObject.MyBO).FullName (or whatever the property is that returns the fully qualified name of a type).
I made a request way back that SF consider changing how they serialize BO names and enum names because of this. I'd be nice if they stopped serializing the names as strings and instead serialized them as the GetType().FullName instead. Of course, this might not be possible. But is would sure be nice if it was (and not just for obfuscation, but for normal refactoring).
Let me know if you have more questions and I'll try to answer them...
