[VB6] problems in a property for activate the timer

i'm trying.. but i'm still more confuse:(
i have the FileName property in my Sprite control...

Code:

---

...If lngTotalSubImages < 1 Then
        Animation = AnimationStopped
        aniAnimation = AnimationStopped
        tmrAnimation.Enabled = False
        tmrAnimation.Interval = 0
    Else
        Animation = AnimationPlay
        aniAnimation = AnimationPlay
        tmrAnimation.Interval = lngChangeImageTime
        tmrAnimation.Enabled = True
    End If....

---

the objective of these if is: if the image is 1 animation(>1) then activate the timer else desactivate it.
the problem is that the timer isn't activated(when is 1 animation):(
i have tested the lngTotalSubImages and it's fine.... why these strange erro?:(
thanks