App Freezes - Never Completes Transformation – Watercolor Effect Art Filters Review

I purchased the app to unlock the additional features and remove the watermark. Each and every time I attempt to transform an image, the progress bar freezes about 1/3 of the way through. After restarting, the same issue continues, regardless of which of the effects I choose. I am running an up to date IOS. Please advise.
Review by cyber_nymph on Watercolor Effect Art Filters.