Does unity3d pro also let you export for free too? can you export as unity3d free from unity3d pro so you can export for free to mobile platforms minus the pro features?
I already got unity3d pro for all the mobile but windows store and black berry
You can only export to any windows app (windows 8/RT/phone) if you have unity pro. You can’t however export to blackberry (even with pro), you need to buy a licence! 
With Unity pro you can export to the following platforms:
Windows 8
Windows RT
Windows Phone
Android
iOS
Google Chrome Native…
Web Player
Flash
PC
MAC
Linux
Just take a look at this page if you want to see yourself.
http://unity3d.com/unity/multiplatform/
If you’re asking about going between Unity Pro and Unity (free) there are no solutions. However, Unity Pro doesn’t do anything for blackberry or windows store.
Both Unity Pro and Unity free can export to iOs and Android now.