Give this a shot. It works here.

Code:
INCLUDE "cdc_desc.bas"
INCLUDE "USB_ASM_Service.pbp"    ' Base Interrupt System


LED       VAR PORTB.0
Buffer    VAR BYTE[10]
Buffer2    VAR BYTE[10]
Cnt       VAR BYTE


i    var byte
ADCON1 = 15               ' Set all I/Os to Digital      
CMCON = 7                 ' Disable Comparators
Cnt = 5
i = 0
'****************************************************
TRISA.4 = 1 ' RA4/T0CKI = input to TMR0 counter
'If you prefer, then increment on low-to-high transitions
T0CON   = 111000        
LOW LED
Loop1:
TMR0L = 0     ' Clear TMR0 count before start   
'**************ADDED COde
gosub usbtx   ' transmit character c to pc
'**************************** 
Loop2:
WHILE TMR0L = 0 ' Wait for high-to-low transition      
WEND           ' on RA4/T0CKI
pause 5
PORTA.2 = 1    ' LED on to indicate transition seen     LED PORTA.2 
i=i+1       ' Clear screen
buffer[0] = 49
Buffer[1] = 13       
USBOut 3, Buffer, 2,Loop2
LOW LED   ' LED off
goto Loop1   


usbtx:
TOGGLE LED
Buffer2[0] = 99
Buffer2[1] = 13       
USBOut 3, Buffer2,2,usbtx
return