StackOverflowException When mocking IList

This is indeed a bug.
But even if the test code would work you'll have to remember that calling "Add" method won't do anything because sv was create using recursive fakes.
tip: in Isolator 5.2.0 Recursive Fakes is the default behavior.
Instead of using WillReturn use WillReturnCollectionValueOf that is intended for what you need:

        [Test, Isolated]
        public void SimpleViewTestOld()
        {
            SimpleView sv = Isolate.Fake.Instance<SimpleView>(Members.ReturnRecursiveFakes);

            var instance = Isolate.Fake.Instance<MyBase>(Members.ReturnRecursiveFakes);
            Isolate.WhenCalled(() => instance.FirstNumber).WillReturn(2.0);
            Isolate.WhenCalled(() => sv.MyInt).WillReturnCollectionValuesOf(
                new List<MyBase>
                {
                    instance
                });

            foreach (var VARIABLE in sv.MyInt)
            {

            }
        }

This is indeed a bug.
But even if the test code would work you'll have to remember that calling "Add" method won't do anything because sv was create using recursive fakes.
tip: in Isolator 5.2.0 Recursive Fakes is the default behavior.
Instead of using WillReturn use WillReturnCollectionValueOf that is intended for what you need:

        [Test, Isolated]
        public void SimpleViewTestOld()
        {
            SimpleView sv = Isolate.Fake.Instance<SimpleView>(Members.ReturnRecursiveFakes);

            var instance = Isolate.Fake.Instance<MyBase>(Members.ReturnRecursiveFakes);
            Isolate.WhenCalled(() => instance.FirstNumber).WillReturn(2.0);
            Isolate.WhenCalled(() => sv.MyInt).WillReturnCollectionValuesOf(
                new List<MyBase>
                {
                    instance
                });

            foreach (var VARIABLE in sv.MyInt)
            {

            }
        }

Thanks Dror, I realized that my code is not valid anyway, just that TestDriven.net shouldn't crash even when my code is invalid.

And your solution was the one that I adopted, thanks for your prompt response. :D
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