The Reverse Engineering (RE) wizard over-writes the Class.OpenAccess.cs/vb file. If you make your changes in the Class.cs/vb file it won't be over-written.
Regarding the m:n relation -
I assume you have 3 tables similar to A,B, AB
1)You can use the RE wizard and map these tables to classes and generate them. So now you have 3 classes - A, B, AB.
2) You can now add a collection of AB instances to both A and B manually.
3) Use the forward mapping dialog and select the 'ab' collection in A and map it to a 1-n collection. Uncheck the 'Use join table' and specify the inverse field 'a' in class AB. Do exactly the same thing for the 'ab' field in Class B
4) You will also need to add the Add, Remove and RemoveInverse methods present in the sample code, manually
I know this is slightly complicated but hope you can achieve what you want now.
the Telerik team
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