Custom Fiori app loads shifted

Hi Experts,

We have a running fiori app, it was developed like a year ago, everyting was fine. Now we have upgraded the gateway to NW 7.5, and this app loads like this:

After refreshing it it get's into its place, but it's really frustrating becouse everytime I reopen it from the launchpad I see this.

Any ideas?

Thanks

David