Alternate form spell not working ??

[operation3000]

Hello,
Here is my problem
I'm trying to make an alternate form spell, like the druid of talon and the druid of claw have. So I made one by using Bear Form spell, but when testing, I click on the spell icon, the icon change, then it came back to the first one and the unit hasn't changed at all.
Does someone can tell me how to make a spell like this or how to fix this bug please?
thanks a lot

 

[mckill2009]

transformations usually includes 2 units and that 2 unit must have the same ability...

 

[operation3000]

Omg, I'm noob, I forgot to add the ability to the alternate unit -.-
Thanks alot^^