When OSCCAL in PIC 12F629 is corrupted, or you want to recalibrate it (there are some circuits and firnware out there to do this), the VM111 does not give you access to set the new OSCCAL value, using PicProg2009. This is worsened by the fact that when it resets code protection and erases the pic, it clobbers OSCCAL. This means that the internal oscilator is therafter of no use as it has lost its factory calibration. Even if you knew what the value was beforehand, you cannot put it back.
Could the software be changed to allow OSCCAL to be set by hand (it could be a special function so people don’t do it by accident).
A temporary workaround is to use ProgPic2 to set the return of the OSCCAL in 0x3ff by burning a program with
org 0x3ff
retlw 0xnn ;where nn is the new calibration rendering 0x34nn as the OSCCAL value
org
Burn this to the pic and the OSCCAL should be set to be used by the PicProg2009 program and other properly written applications, but this is just a workaround. 
Note that you cannot burn the above using PicProg2009, you have to use progpic2, then you can burn your proper program using PicProg2009.