Wrong example code on the main project page.

[AvilinTsimafei]

instead of
FuzzyStringComparisonTolerance tolerance = FuzzyStringTolerance.Strong;
bool result = source.ApproximatelyEquals(target, options, tolerance);

it should be:
FuzzyStringComparisonTolerance tolerance = FuzzyStringComparisonTolerance.Strong;
bool result = source.ApproximatelyEquals(target, tolerance, options.ToArray());

[joffremota]

Old issue, but don't think so.

ApproximatelyEquals expects string, List of options, tolerance, at this order.