Bitmap import bug

The manual says that Halion 6 can create a bitmap from multiple image files and import a bitmap that has up 255 frames. Whenever I try to import or create a bitmap that has over 64 frames I get an empty render within Halion even though the file seems to be correct. I’ve attached an image showing a multi-frame bitmap created by Halion. In one picture it rendered perfectly fine and in the second picture I added one more frame and it did not render properly in Halion. This is using W10 64bit.
Screenshot (52).png
Screenshot (51).png