The most likely cause is a slow Internet connection. Maybe the firewall blocked the loading of some scripts from third party servers (Yandex, VKontakte, Facebook). Be patient and wait for a bit.
Most likely they did not have time to load because of slow, overloaded channel to Internet. When the page loads, or changing themes should wait at least a few seconds. It is not recommended to perform any action with images (to scroll the list to select, change the subject) until such time as not to download the image for the current theme (this can lead to incorrect operation of the page). The number of images is large (some over 1000), they are stored on a separate public server and at some point he may be busy. Be patient and wait for a bit.
If there is a checkbox "Add music", but when you click on the "Play" button nothing happens. You should check if the column shows whether the volume if you hear the ears. If everything is in order, then it could be either outdated browser's security settings or a missing flash plugin. To check you must go to this link. Green labels "OK" indicate successful completion of testing.
If you found a ready-made postcard that you liked. If you want to change the labels on it. It's very easy! For this you need to copy the address of the card and on this page insert it into the top field. Then, click «Convert» or «Edit card». You can change the card almost everything as you like.
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