I think this is a known bug in 5.1.5 on Android and will be dealt with in the next formal release:
Transforming all layers of any type of file into white screens - #2 by Sooz
Given that it’s marked as Fixed in the bug tracker, you should be able to download and sideload the nightly build .apk.
I don’t know how to do that but someone else could give advice.
An alternative would be the 5.1.4 .apk.