As it is working in the Layout Designer but not in the Player we need to try and extract the downloaded, formatted content from the Player library.
These are stored as .htm files in the local player library and are prefixed with a long ID. How many htm files you have will depend on the number of layouts/regions you have.
Your clock will have the following inside it (amongst other things)
<span class="clock" format="dddd DD MMMM YYYY HH:mm"></span>
Can you look through each one until you find your clock and then paste the contents of the file here between code tags?