@Kyle
At this moment, our app doesn't support direct file export. However, I'm pleased to inform you that there are alternative solutions available.

You can find the STL files you're looking for on the following websites:

Thingiverse - [https://www.thingiverse.com/] Cults3D - [https://cults3d.com/] Free3D - [https://free3d.com/]

the steps are as follows

Choose the template you like, download it and save it on your desktop. Download Wiibuilder from the SD card. Open Wiibuidier and open the model (STL). Adjust the model to an appropriate size. Select Slices. After the section, choose to save, it is recommended to save to desktop. Insert the SD card into the card reader. Insert the card reader into the computer. Copy and paste the template file (G.CODE) to the SD card. Insert the SD card into the printer, select the model and start printing.

We have a video about the how to use wiibuilder and you can take it for a reference.
https://drive.google.com/open?id=1rsDPfVNea8LH15euoTUHQjiW2d6LKDb1&authuser=luzhicheng970322%40gmail.com&usp=drive_fs