I will make sure clicking on the screen does not cancel the operation.
Just to make sure, are some of the Minifigures Collectible (Series 1-15, etc)?
Can you share a screenshot of your Brickset minifigures, and possibly of what the app is saying?
Feel free to email firstname.lastname@example.org
I will ensure that clicking on the screen does not cancel the operation, but unless there are more details on what doesn't upload, I don't think I can investigate that part of this suggestion any further.
I haven't seen any problems with exports while testing. Can you describe how many minifigs are being uploaded?
Does it always skip the same minifigs?
Are there any error messages displayed?
Would love to add this, but will need help in coming up with guide. Any known existing guides?
Will consider this if there are more votes.