If you see blank puzzles/black pieces or if you can't open the app at all after transferring to another IOS device, downloading from the cloud or after the app/IOS update, please follow the instruction:
Please reinstall the app: delete it and download from the App Store again.
Please make sure that you are registered in the app before reinstallation.
If you are registered (!), your coins, levels and packs will be saved. Started, downloaded from Jigsaw Puzzle Feed and created puzzles will be lost.
After reinstallation please log in the app under your account (the same e-mail or Facebook you used for registration before) and restore packs: My account (=envelope icon in the upper bar) -> Packs -> hit Restore button on the pack.
To restore Gold Pack/All inclusive and other paid purchases made with money you should click on the Restore All Paid Downloads button and reboot your device (this is an important step).
If you use the same Apple ID you may repurchase the packs for FREE.