| Revision no. | Date | Author | Comments |
| 0.1 | HB | draft | |
| 1.0 | HB | submitted for task approval | |
| 1.1 | 1998/11/06 | HB | minor changes |
| 1.2 | 1999/07/12 | HB | parameter names changed |
| 1.3 | 1999/09/20 | HB | BOX_SIZE dependence of cut-out radius |
| removed from description. | |||
| 1.8 | 2000/01/25 | HB | version number set to code version number |
| 2.0 | 2000/09/25 | HB | number of spline nodes now user selectable |
| 2.1 | 2000/12/20 | HB | description of parameter mlmin |
| 2.2 | 2001/01/15 | HB | new keyword NDOF mentioned |
| 2.3 | 2001/01/26 | HB | description of new/redefined parameters |
| 2.4 | 2001/03/16 | HB | parameter idinst removed |
| 2.7 | 2002/01/09 | HB | default values of withexpimage and withdetmask changed |
| 3.2 | 2002/04/15 | GL | included out of time events in background map |
| 3.5 | 2003/06/29 | GL | extended task description in response to SPRs SSC-SPR-3075, SSC-SPR-3012 |
| 4.0.2 | 2004/02/25 | GL | Describe new option ``fitmethod=model'' |