Hmm. . . I"m sorry that is happening. I know that sometimes the export can hang if the animation is too long, but I think yours should be fine.
How many frames is it? How much ram is on your machine? The last few percent of the export dialog is actually encoding the frames into a video. There might be a chance that it is running out of ram in the process.
One option to try is to duplicate the ENTIRE project folder. And open one of the copies in Arlo and delete the first half of the animation. In the other copy you could delete the last half. And then export each half and put them together in a video editing software.
Another option to try- Arlo has an export as image sequence option. You could do that and then import the sequence into a video editor. You would need to change the frame rate of the video project to match the frame rate in Arlo.
Please keep me posted about how things go. I'm working on an update that I hope to have out soon.
Take care!