Hey thank you! I appreciate hearing that greatly! :D
That's a known but weirdly undiagnosable bug that happens at random. Basically: when you're grabbing onto items then all other detections (like grabbing onto ladders) will be disabled so that you don't grab onto ladders twice. For some reason, something doesn't re-enable that detection.
I have been working on a new polished version which strips the project of UFPS (code responsible for camera movement and animations... and it caused a lot of problems too) so that problem is gone, but it will take a long time until the new version is done as I intend it to have a different logic and hopefully a way out. If I'm lucky and have the time, it may have something else as well.
Sorry for late reply (I'm away from home)