Hello, I found that the fishing rod line, which is what this mod uses to render I believe, often goes invisible if it is thrown too far, or just as one is swinging.
I would suggest making it so that it renders a thicker line and that it be tweaked so it never goes invisible.
I know this would be difficult though, so no pressure.

Are you using the newest version? I changed it. It uses the renderer for the lead and it only disappears when you aren't looking at it or it's in an unrendered chunk.

The renderer was rewritten in v7 (for 1.9.4 and 1.8.9). Try using one of these versions and see if you still have the problem.

Latest version for 1.7.10. It disappears when it is 4-6 chunks away. My render distance is set at 16.

I am using this mod in a Private mod pack (only me and 1 friend use it, it isnt being distributed) which is for version 1.7.10. I tested those versions, they do solve the problem :/
Unfortunately Im stuck on 1.7.10 due to other mods not being updated.