CASE statement in a where clause for multi valued parameter

Hey all,

I have a stored procedure that forms my report body. I have 3 parameters. FromDate, ToDate and Status.

Some of the fields are Id,RedDate,Value,Status

I have declare the params as:

@FDate DATE = NULL,
@TDate DATE = NULL,
@Status = VARCHAR(MAX)

In my select statement I have something like this:

Select Id,Value,RedDate,Case when rf like '%Renew%' then 'R' else [State] End As [Status]  From MyTable
Where
CONVERT(DATE,RedDate) BETWEEN Coalesce(@FDate,RedDate) AND Coalesce(@TDate,RedDate)
OR @FDate IS NULL
OR @TDate IS NULL
And (Case When rf like '%Renew%' then 'R' else [State] End IN
(SELECT VALUE FROM dbo.ufn_Split(@Status,',')) OR '!All' IN (@Status))

Now, RedDate will have value only if st='R', if the value is anything other than 'R', then RedDate value is NULL. That's the reason I have declared the date parameters as NULLS.

Problem is, when I execute my stored procedure by passing the following values it gives me all the results and not the ones that I actually want. Here is how I execute my stored proc: