Would you try this trick?

Don't bound textbox to any table/cursor field, just give real value to the textbox when cursor movement
And leave InputMask property as blank

*!*
*!* your cusor movement or controlsource assigned
*!*
thisform.text1.Value = yourcursor.field_name  && this is char type field
thisform.text2.ControlSource = "yourcursor.another_field_name" 


*!*
*!* text1.gotfocus event
*!*
this.Value = VAL(this.Value)
this.InputMask = [99999.99]

*!*
*!* text1.lostfocus event
*!*
IF this.Value > 0
  this.Value = TRANSFORM(this.Value)
ELSE
  this.Value = ""
ENDIF
this.InputMask = ""
*!* you can update the change to table/cursor here
REPLACE yourcursor.field_name WITH this.Value