I'm currently tracking an issue in the current versions of Velocity Lapse where the last capture image does not save properly and results in a "broken project".
You may find that a project shows a message like:
RECOVERED PROJECT It was detected that this project contains broken images. You may be able to recover the images via a file manager.
This is the fallback when this issue is encountered. In most cases you can tap the project and view/export your project like normal. If not you can use a PC to access the /storage/emulated/0/Android/data/com.velocitylapse.velocitylapse folder and retrieve your time-lapse.
Sorry for any inconvenience and thank you for your patience as I work to resolve this issue. Feel free to submit your reports below.