state machine not holding variable value outside state

Following the behavior of your code is difficult (for me at least) due to your use of a large collection of signals in the sensitivity list. Try working with just one process using the following framework:

    PROCESS (Sclk, reset )  --do not add items here
    BEGIN        
        IF (reset = '0') THEN
          --put everything you want to initialize/re-initialize here
        ELSIF (rising_edge (Sclk)) THEN    
          --put ALL of your other code here
        END IF;
    END PROCESS;