As Lancer has said it was something that simply never got made. It clearly got quite far along but was then cancelled. I believe storyboarding and concept was as far as it went and there was never any actual media released (or at least none we have ever seen).
It was no doubt a change in marketing plan (in budget and/or direction) by Hasbro. The expense of a full cartoon movie release was clearly not going to equate enough for them to go with it. So the lines media support moved to the straight to VHS/DVD featurettes. These kind of changes happen a lot during marketing build up unfortunately and normally for reasons we can only ever hazard a guess on.