Hello again,
Thanks to DT's advice I was able to get my elapsed timer test program working well. I modified the original Elasped_INT routine in order to keep track of time in seconds and tenths of seconds to suit my purpose. My test circuit using this program worked perfectly, with good accuracy when checked against a stopwatch.

However, when adding another interrupt source there was no response from the breadboard circuit. The new source was RAC_INT, interrupt on portA change. The circuit has switches on several portA pins. Input changes on the pins was verified, but the test progarm did not respond as expected.

Code:
 'device is PIC 16F684

'set registers
        OPTION_REG.7 = 0     'enable porta pullups    
        CMCON0 = 7           'comparators off
        ANSEL = 0            'porta pins all digital 
        TRISA = %111111      'set porta pins as input
        TRISC = %001101      'set portc pins 0,2,3 as input, all others output
        OSCCON = %1110000    'set internal osc. at 8 mhz, wait for stable freq.
        OSCTUNE = 0          'internal osc. running at factory calibration

        DEFINE OSC 8         '8 Mhz oscillator

        while OSCCON.2 = 0   'wait for osc.to be stable
        wend

'declare variables
        led     var portc.3      'led output on portc.3
        DTtime  var word
        sum     var word    

start:   
        low led      'flash red LED for 0.5 sec
        pause 500
        input led  

        pause 2000   'pause 2 seconds
        
INCLUDE "DT_INTS-14 for F684.bas" 'Base interrupt with wsave selected for 16F684
INCLUDE "ReEnterPBP.bas"          'Using PBP interrupts
INCLUDE "Elapsed_INT_RI.bas" 'Elasped timer counting seconds and tenths seconds

ASM
INT_LIST  macro    ; IntSource,        Label,  Type, ResetFlag?
        INT_Handler   TMR1_INT,  _ClockCount,   PBP,  yes
        INT_Handler   RAC_INT,   _RDT,          PBP,  yes
    endm
    INT_CREATE            ; Creates the interrupt processor

    INT_ENABLE  TMR1_INT  ; Enable Timer 1 Interrupts  
    INT_ENABLE  RAC_INT   ; Enable PortA Change Interrupt
ENDASM

DTtime = 1800             ' 180.0 second test
Gosub ResetTime          ' Reset Time to  0d-00:00:00.00
Gosub StartTimer          ' Start the Elapsed Timer

Main:
    low Led               'turn on led
    sum = 10*Seconds + Tenths
    if sum => DTtime then
    high led              'turn off led
    goto halt
    endif
GOTO Main

'-------Interrupt Handler for RDT------------
RDT:
   low led              'turn led on
   pause 2000        'pause 2 seconds
@ INT_RETURN
'---------------------------------------------
halt: end
427 words