Nokia has updated their Maps app for Windows Phone 8 devices to version 126.96.36.199. This new version brings performance improvements and bug fixes. More than anything, it fixed the app startup issue for many people. Nokia posted the following information about the startup issue,
Microsoft fixed the Windows Store issue that prevented Nokia Maps from starting – you should no longer see the ‘Problem with app’ dialogue when updating to this version. We’re very sorry for any inconvenience caused.
You can download Nokia Maps from your Lumia WP8 device here.